diff --git a/specification/commerce/cspell.yaml b/specification/commerce/cspell.yaml
new file mode 100644
index 000000000000..99cdfc20f70f
--- /dev/null
+++ b/specification/commerce/cspell.yaml
@@ -0,0 +1,11 @@
+# This file configures spell checking. Items in "words" were initially populated
+# with words that might be spelling errors. Review these words and take
+# appropriate action. For more information, see: https://aka.ms/ci-fix#spell-check
+
+# Spell checking is not case sensitive
+# Keep word lists in alphabetical order so the file is easier to manage
+version: '0.2'
+import:
+  - ../../cspell.yaml
+words:
+  - upns
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Operations_List.json b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Operations_List.json
new file mode 100644
index 000000000000..a696d0e3987f
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Operations_List.json
@@ -0,0 +1,35 @@
+{
+  "parameters": {
+    "api-version": "2026-04-24-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "value": [
+          {
+            "name": "Microsoft.Commerce/upns/read",
+            "display": {
+              "provider": "Microsoft.Commerce",
+              "resource": "upns",
+              "operation": "Get UPN",
+              "description": "Returns a single UPN (Unified Product Node) resource by its GUID identifier."
+            },
+            "isDataAction": false
+          },
+          {
+            "name": "Microsoft.Commerce/upns/list/action",
+            "display": {
+              "provider": "Microsoft.Commerce",
+              "resource": "upns",
+              "operation": "List UPNs",
+              "description": "Lists UPN (Unified Product Node) resources at tenant/provider scope."
+            },
+            "isDataAction": false
+          }
+        ]
+      }
+    }
+  },
+  "operationId": "Operations_List",
+  "title": "List all operations supported by Microsoft.Commerce/OfferCatalog"
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Upns_Get.json b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Upns_Get.json
new file mode 100644
index 000000000000..150db3c7e4e5
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Upns_Get.json
@@ -0,0 +1,48 @@
+{
+  "title": "Get a UPN by its GUID identifier.",
+  "operationId": "Upns_Get",
+  "parameters": {
+    "api-version": "2026-04-24-preview",
+    "upnGuid": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+    "fragments": "pricing,display"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "id": "/providers/Microsoft.Commerce/upns/5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+        "name": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+        "type": "Microsoft.Commerce/upns",
+        "systemData": {
+          "lastModifiedAt": "2026-04-15T12:00:00Z"
+        },
+        "properties": {
+          "valueExchange": {
+            "id": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+            "unit": {
+              "hint": "vCPU Duration - 1 Hour"
+            },
+            "dimensions": {
+              "location": "westus2",
+              "feature": "linux"
+            }
+          },
+          "product": {
+            "id": "DZH318Z0BQV6",
+            "friendlyName": "Container Instances",
+            "template": "offer-template/az-generic",
+            "tags": {
+              "service": "compute"
+            },
+            "ownership": "1PP"
+          },
+          "sku": {
+            "id": "DZH318TNL8K4",
+            "friendlyName": "Standard",
+            "type": "consumption"
+          },
+          "template": "offer-template/az-generic"
+        }
+      }
+    }
+  }
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Upns_ListByTenant.json b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Upns_ListByTenant.json
new file mode 100644
index 000000000000..e19fbbb4a532
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/examples/2026-04-24-preview/Upns_ListByTenant.json
@@ -0,0 +1,86 @@
+{
+  "title": "List UPNs at tenant/provider scope.",
+  "operationId": "Upns_ListByTenant",
+  "parameters": {
+    "api-version": "2026-04-24-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "value": [
+          {
+            "id": "/providers/Microsoft.Commerce/upns/5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+            "name": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+            "type": "Microsoft.Commerce/upns",
+            "systemData": {
+              "lastModifiedAt": "2026-04-15T12:00:00Z"
+            },
+            "properties": {
+              "valueExchange": {
+                "id": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+                "unit": {
+                  "hint": "vCPU Duration - 1 Hour"
+                },
+                "dimensions": {
+                  "location": "westus2",
+                  "feature": "linux"
+                }
+              },
+              "product": {
+                "id": "DZH318Z0BQV6",
+                "friendlyName": "Container Instances",
+                "template": "offer-template/az-generic",
+                "tags": {
+                  "service": "compute"
+                },
+                "ownership": "1PP"
+              },
+              "sku": {
+                "id": "DZH318TNL8K4",
+                "friendlyName": "Standard",
+                "type": "consumption"
+              },
+              "template": "offer-template/az-generic"
+            }
+          },
+          {
+            "id": "/providers/Microsoft.Commerce/upns/7b2f9a1c-1234-4567-89ab-cdef01234567",
+            "name": "7b2f9a1c-1234-4567-89ab-cdef01234567",
+            "type": "Microsoft.Commerce/upns",
+            "systemData": {
+              "lastModifiedAt": "2026-04-14T09:30:00Z"
+            },
+            "properties": {
+              "valueExchange": {
+                "id": "7b2f9a1c-1234-4567-89ab-cdef01234567",
+                "unit": {
+                  "hint": "Subscription - 1 Month"
+                },
+                "dimensions": {
+                  "location": "global",
+                  "feature": "premium"
+                }
+              },
+              "product": {
+                "id": "DZH318Z0BPWH",
+                "friendlyName": "Virtual Machines Ev3 Windows",
+                "template": "offer-template/az-vm",
+                "tags": {
+                  "service": "compute"
+                },
+                "ownership": "1PP"
+              },
+              "sku": {
+                "id": "DZH318Z0BPWH-E16",
+                "friendlyName": "Standard E16s v3",
+                "type": "consumption"
+              },
+              "template": "offer-template/az-vm"
+            }
+          }
+        ],
+        "nextLink": "https://management.azure.com/providers/Microsoft.Commerce/upns?api-version=2026-04-24-preview&$skipToken=abc123"
+      }
+    }
+  }
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/main.tsp b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/main.tsp
new file mode 100644
index 000000000000..27af9b7b67e8
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/main.tsp
@@ -0,0 +1,30 @@
+import "@typespec/http";
+import "@typespec/rest";
+import "@typespec/versioning";
+import "@azure-tools/typespec-azure-core";
+import "@azure-tools/typespec-azure-resource-manager";
+import "./models.tsp";
+import "./upns.tsp";
+
+using TypeSpec.Http;
+using TypeSpec.Rest;
+using TypeSpec.Versioning;
+using Azure.Core;
+using Azure.ResourceManager;
+
+/** Microsoft.Commerce OfferCatalog Resource Provider management API. */
+@armProviderNamespace("Microsoft.Commerce")
+@service(#{ title: "Microsoft Commerce Offer Catalog" })
+@versioned(Microsoft.Commerce.Versions)
+namespace Microsoft.Commerce;
+
+/** The available API versions for the Offer Catalog service. */
+enum Versions {
+  /** The 2026-04-24-preview API version. */
+  @armCommonTypesVersion(Azure.ResourceManager.CommonTypes.Versions.v6)
+  @previewVersion
+  v2026_04_24_preview: "2026-04-24-preview",
+}
+
+/** The operations supported by the Microsoft.Commerce resource provider for the Offer Catalog service. */
+interface Operations extends Azure.ResourceManager.Operations {}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/models.tsp b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/models.tsp
new file mode 100644
index 000000000000..1a5ac214b122
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/models.tsp
@@ -0,0 +1,196 @@
+import "@typespec/http";
+import "@typespec/rest";
+import "@azure-tools/typespec-azure-core";
+import "@azure-tools/typespec-azure-resource-manager";
+
+using TypeSpec.Http;
+using Azure.Core;
+using Azure.ResourceManager;
+
+namespace Microsoft.Commerce;
+
+/**
+ * Ownership classification of a product. Indicates whether the product is
+ * owned by Microsoft (first-party) or by a third-party publisher.
+ */
+union UpnOwnership {
+  string,
+
+  /** First-party (Microsoft-owned) product. */
+  "1PP",
+
+  /** Third-party (publisher-owned) product. */
+  "3PP",
+}
+
+/** The commercial type of a SKU. */
+union SkuType {
+  string,
+
+  /** Consumption-based SKU (pay-as-you-go). */
+  Consumption: "consumption",
+
+  /** Subscription-based SKU. */
+  Subscription: "subscription",
+
+  /** One-time purchase SKU. */
+  OneTime: "one_time",
+}
+
+/**
+ * Fragment names that can be requested via the `fragments` query parameter
+ * on UPN read operations. Each fragment is an opt-in subtree exposed under
+ * `properties.{fragmentName}` in the response.
+ */
+union UpnFragment {
+  string,
+
+  /** Listing and catalog-presentation fragment. */
+  Listing: "listing",
+
+  /** List / retail / rate-card pricing fragment (not customer-negotiated pricing). */
+  Pricing: "pricing",
+
+  /** Purchase flow configuration fragment. */
+  Purchase: "purchase",
+
+  /** Lifecycle metadata fragment. */
+  Lifecycle: "lifecycle",
+
+  /** Display metadata fragment. */
+  Display: "display",
+
+  /** Tax configuration fragment. */
+  Tax: "tax",
+
+  /** Term and billing-plan fragment. */
+  Term: "term",
+
+  /** Benefits fragment. */
+  Benefits: "benefits",
+
+  /** Bundle composition fragment. */
+  Bundle: "bundle",
+
+  /** Eligibility predicates fragment. */
+  Eligibility: "eligibility",
+
+  /** Compact channel/market/salesMotion permutations fragment. */
+  Permutations: "permutations",
+
+  /** Catalog tags fragment. */
+  Tags: "tags",
+
+  /** Search keywords fragment. */
+  Search: "search",
+
+  /** Financial classification fragment. */
+  Financial: "financial",
+
+  /** External identifiers fragment. */
+  ExternalIds: "externalIds",
+}
+
+/** Unit metadata associated with a value exchange. */
+model ValueExchangeUnit {
+  /** A human-readable hint describing the unit (for example, "vCPU Duration - 1 Hour"). */
+  hint?: string;
+}
+
+/** Dimension metadata associated with a value exchange. */
+model ValueExchangeDimensions {
+  /** The location dimension (for example, an Azure region). */
+  location?: string;
+
+  /** The feature dimension (for example, a product feature name). */
+  feature?: string;
+}
+
+/**
+ * Value-exchange (UPN identity) metadata. The value exchange is the leaf of
+ * the OCP Product -> SKU -> Value Exchange hierarchy and is the transactable
+ * identity addressed by this resource.
+ */
+model ValueExchange {
+  /** The stable identifier of the value exchange. */
+  id: string;
+
+  /** Unit metadata for the value exchange. */
+  unit?: ValueExchangeUnit;
+
+  /** Dimension metadata for the value exchange. */
+  dimensions?: ValueExchangeDimensions;
+}
+
+/**
+ * Denormalized product summary embedded in a UPN. Only identifying and
+ * discovery-relevant product fields are exposed here; the full product
+ * document is not retrievable as a separate resource type.
+ */
+model ProductSummary {
+  /** The stable product identifier. */
+  id: string;
+
+  /** The human-readable friendly name of the product. */
+  friendlyName?: string;
+
+  /** The offer template identifier for this product (for example, "offer-template/az-generic"). */
+  template?: string;
+
+  /** Discovery tags associated with the product. */
+  #suppress "@azure-tools/typespec-azure-resource-manager/arm-no-record" "Product tags are free-form discovery metadata sourced from the upstream BigCat catalog; the key set is unbounded and cannot be modeled as an explicit type."
+  tags?: Record<string>;
+
+  /** Ownership classification of the product. */
+  ownership?: UpnOwnership;
+}
+
+/**
+ * Denormalized SKU summary embedded in a UPN. Only identifying and
+ * discovery-relevant SKU fields are exposed here.
+ */
+model SkuSummary {
+  /** The stable SKU identifier. */
+  id: string;
+
+  /** The human-readable friendly name of the SKU. */
+  friendlyName?: string;
+
+  /** The commercial type of the SKU. */
+  type?: SkuType;
+}
+
+/**
+ * Properties of a UPN (Unified Product Node) resource. A UPN is the
+ * transactable catalog identity and carries denormalized product and SKU
+ * summaries plus the value-exchange identity.
+ */
+#suppress "@azure-tools/typespec-azure-resource-manager/arm-resource-provisioning-state" "UPN is a read-only catalog projection synthesized from the upstream BigCat feed; no ARM provisioning lifecycle applies. The resource has no create/update/delete operations and therefore no provisioning state to track."
+model UpnProperties {
+  /** The value-exchange identity that this UPN represents. */
+  valueExchange: ValueExchange;
+
+  /** Denormalized product summary. */
+  product: ProductSummary;
+
+  /** Denormalized SKU summary. */
+  sku: SkuSummary;
+
+  /** The offer-template identifier for this UPN (for example, "offer-template/az-vm"). */
+  template?: string;
+}
+
+/**
+ * Optional query parameter that allows callers to opt in to fragment
+ * subtrees on UPN read operations. The value is a comma-separated list of
+ * fragment names (see `UpnFragment`), or `*` to request all fragments.
+ * Default (omitted) returns only the identity envelope.
+ */
+model FragmentsQueryParameter {
+  /**
+   * A comma-separated list of fragment names to include in the response,
+   * or `*` to include all fragments. Example: `pricing,permutations,display`.
+   */
+  @query("fragments")
+  fragments?: string;
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Operations_List.json b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Operations_List.json
new file mode 100644
index 000000000000..a696d0e3987f
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Operations_List.json
@@ -0,0 +1,35 @@
+{
+  "parameters": {
+    "api-version": "2026-04-24-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "value": [
+          {
+            "name": "Microsoft.Commerce/upns/read",
+            "display": {
+              "provider": "Microsoft.Commerce",
+              "resource": "upns",
+              "operation": "Get UPN",
+              "description": "Returns a single UPN (Unified Product Node) resource by its GUID identifier."
+            },
+            "isDataAction": false
+          },
+          {
+            "name": "Microsoft.Commerce/upns/list/action",
+            "display": {
+              "provider": "Microsoft.Commerce",
+              "resource": "upns",
+              "operation": "List UPNs",
+              "description": "Lists UPN (Unified Product Node) resources at tenant/provider scope."
+            },
+            "isDataAction": false
+          }
+        ]
+      }
+    }
+  },
+  "operationId": "Operations_List",
+  "title": "List all operations supported by Microsoft.Commerce/OfferCatalog"
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Upns_Get.json b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Upns_Get.json
new file mode 100644
index 000000000000..150db3c7e4e5
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Upns_Get.json
@@ -0,0 +1,48 @@
+{
+  "title": "Get a UPN by its GUID identifier.",
+  "operationId": "Upns_Get",
+  "parameters": {
+    "api-version": "2026-04-24-preview",
+    "upnGuid": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+    "fragments": "pricing,display"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "id": "/providers/Microsoft.Commerce/upns/5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+        "name": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+        "type": "Microsoft.Commerce/upns",
+        "systemData": {
+          "lastModifiedAt": "2026-04-15T12:00:00Z"
+        },
+        "properties": {
+          "valueExchange": {
+            "id": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+            "unit": {
+              "hint": "vCPU Duration - 1 Hour"
+            },
+            "dimensions": {
+              "location": "westus2",
+              "feature": "linux"
+            }
+          },
+          "product": {
+            "id": "DZH318Z0BQV6",
+            "friendlyName": "Container Instances",
+            "template": "offer-template/az-generic",
+            "tags": {
+              "service": "compute"
+            },
+            "ownership": "1PP"
+          },
+          "sku": {
+            "id": "DZH318TNL8K4",
+            "friendlyName": "Standard",
+            "type": "consumption"
+          },
+          "template": "offer-template/az-generic"
+        }
+      }
+    }
+  }
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Upns_ListByTenant.json b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Upns_ListByTenant.json
new file mode 100644
index 000000000000..e19fbbb4a532
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/examples/Upns_ListByTenant.json
@@ -0,0 +1,86 @@
+{
+  "title": "List UPNs at tenant/provider scope.",
+  "operationId": "Upns_ListByTenant",
+  "parameters": {
+    "api-version": "2026-04-24-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "value": [
+          {
+            "id": "/providers/Microsoft.Commerce/upns/5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+            "name": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+            "type": "Microsoft.Commerce/upns",
+            "systemData": {
+              "lastModifiedAt": "2026-04-15T12:00:00Z"
+            },
+            "properties": {
+              "valueExchange": {
+                "id": "5ac17b8c-6ac2-432a-b1a9-baa1774c70c5",
+                "unit": {
+                  "hint": "vCPU Duration - 1 Hour"
+                },
+                "dimensions": {
+                  "location": "westus2",
+                  "feature": "linux"
+                }
+              },
+              "product": {
+                "id": "DZH318Z0BQV6",
+                "friendlyName": "Container Instances",
+                "template": "offer-template/az-generic",
+                "tags": {
+                  "service": "compute"
+                },
+                "ownership": "1PP"
+              },
+              "sku": {
+                "id": "DZH318TNL8K4",
+                "friendlyName": "Standard",
+                "type": "consumption"
+              },
+              "template": "offer-template/az-generic"
+            }
+          },
+          {
+            "id": "/providers/Microsoft.Commerce/upns/7b2f9a1c-1234-4567-89ab-cdef01234567",
+            "name": "7b2f9a1c-1234-4567-89ab-cdef01234567",
+            "type": "Microsoft.Commerce/upns",
+            "systemData": {
+              "lastModifiedAt": "2026-04-14T09:30:00Z"
+            },
+            "properties": {
+              "valueExchange": {
+                "id": "7b2f9a1c-1234-4567-89ab-cdef01234567",
+                "unit": {
+                  "hint": "Subscription - 1 Month"
+                },
+                "dimensions": {
+                  "location": "global",
+                  "feature": "premium"
+                }
+              },
+              "product": {
+                "id": "DZH318Z0BPWH",
+                "friendlyName": "Virtual Machines Ev3 Windows",
+                "template": "offer-template/az-vm",
+                "tags": {
+                  "service": "compute"
+                },
+                "ownership": "1PP"
+              },
+              "sku": {
+                "id": "DZH318Z0BPWH-E16",
+                "friendlyName": "Standard E16s v3",
+                "type": "consumption"
+              },
+              "template": "offer-template/az-vm"
+            }
+          }
+        ],
+        "nextLink": "https://management.azure.com/providers/Microsoft.Commerce/upns?api-version=2026-04-24-preview&$skipToken=abc123"
+      }
+    }
+  }
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/offerCatalog.json b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/offerCatalog.json
new file mode 100644
index 000000000000..8a54a7c44ce1
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/preview/2026-04-24-preview/offerCatalog.json
@@ -0,0 +1,496 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "Microsoft Commerce Offer Catalog",
+    "version": "2026-04-24-preview",
+    "description": "Microsoft.Commerce OfferCatalog Resource Provider management API.",
+    "x-typespec-generated": [
+      {
+        "emitter": "@azure-tools/typespec-autorest"
+      }
+    ]
+  },
+  "schemes": [
+    "https"
+  ],
+  "host": "management.azure.com",
+  "produces": [
+    "application/json"
+  ],
+  "consumes": [
+    "application/json"
+  ],
+  "security": [
+    {
+      "azure_auth": [
+        "user_impersonation"
+      ]
+    }
+  ],
+  "securityDefinitions": {
+    "azure_auth": {
+      "type": "oauth2",
+      "description": "Azure Active Directory OAuth2 Flow.",
+      "flow": "implicit",
+      "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
+      "scopes": {
+        "user_impersonation": "impersonate your user account"
+      }
+    }
+  },
+  "tags": [
+    {
+      "name": "Operations"
+    },
+    {
+      "name": "Upns"
+    }
+  ],
+  "paths": {
+    "/providers/Microsoft.Commerce/operations": {
+      "get": {
+        "operationId": "Operations_List",
+        "tags": [
+          "Operations"
+        ],
+        "description": "List the operations for the provider",
+        "parameters": [
+          {
+            "$ref": "../../../../../../common-types/resource-management/v6/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "../../../../../../common-types/resource-management/v6/types.json#/definitions/OperationListResult"
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "../../../../../../common-types/resource-management/v6/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-examples": {
+          "List all operations supported by Microsoft.Commerce/OfferCatalog": {
+            "$ref": "./examples/Operations_List.json"
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    },
+    "/providers/Microsoft.Commerce/upns": {
+      "get": {
+        "operationId": "Upns_ListByTenant",
+        "tags": [
+          "Upns"
+        ],
+        "description": "List UPN resources at tenant/provider scope. Returns the identity\nenvelope for each UPN by default; use the `fragments` query parameter\nto opt in to additional fragment subtrees on every listed UPN.",
+        "parameters": [
+          {
+            "$ref": "../../../../../../common-types/resource-management/v6/types.json#/parameters/ApiVersionParameter"
+          },
+          {
+            "$ref": "#/parameters/FragmentsQueryParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "#/definitions/UpnListResult"
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "../../../../../../common-types/resource-management/v6/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-examples": {
+          "List UPNs at tenant/provider scope.": {
+            "$ref": "./examples/Upns_ListByTenant.json"
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    },
+    "/providers/Microsoft.Commerce/upns/{upnGuid}": {
+      "get": {
+        "operationId": "Upns_Get",
+        "tags": [
+          "Upns"
+        ],
+        "description": "Get a single UPN resource by its GUID identifier. Returns the identity\nenvelope of the UPN.",
+        "parameters": [
+          {
+            "$ref": "../../../../../../common-types/resource-management/v6/types.json#/parameters/ApiVersionParameter"
+          },
+          {
+            "name": "upnGuid",
+            "in": "path",
+            "description": "The GUID identifier of the UPN. Corresponds to the OCP value-exchange productCode.",
+            "required": true,
+            "type": "string",
+            "pattern": "^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "#/definitions/Upn"
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "../../../../../../common-types/resource-management/v6/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-examples": {
+          "Get a UPN by its GUID identifier.": {
+            "$ref": "./examples/Upns_Get.json"
+          }
+        }
+      }
+    }
+  },
+  "definitions": {
+    "ProductSummary": {
+      "type": "object",
+      "description": "Denormalized product summary embedded in a UPN. Only identifying and\ndiscovery-relevant product fields are exposed here; the full product\ndocument is not retrievable as a separate resource type.",
+      "properties": {
+        "id": {
+          "type": "string",
+          "description": "The stable product identifier."
+        },
+        "friendlyName": {
+          "type": "string",
+          "description": "The human-readable friendly name of the product."
+        },
+        "template": {
+          "type": "string",
+          "description": "The offer template identifier for this product (for example, \"offer-template/az-generic\")."
+        },
+        "tags": {
+          "type": "object",
+          "description": "Discovery tags associated with the product.",
+          "additionalProperties": {
+            "type": "string"
+          }
+        },
+        "ownership": {
+          "$ref": "#/definitions/UpnOwnership",
+          "description": "Ownership classification of the product."
+        }
+      },
+      "required": [
+        "id"
+      ]
+    },
+    "SkuSummary": {
+      "type": "object",
+      "description": "Denormalized SKU summary embedded in a UPN. Only identifying and\ndiscovery-relevant SKU fields are exposed here.",
+      "properties": {
+        "id": {
+          "type": "string",
+          "description": "The stable SKU identifier."
+        },
+        "friendlyName": {
+          "type": "string",
+          "description": "The human-readable friendly name of the SKU."
+        },
+        "type": {
+          "$ref": "#/definitions/SkuType",
+          "description": "The commercial type of the SKU."
+        }
+      },
+      "required": [
+        "id"
+      ]
+    },
+    "SkuType": {
+      "type": "string",
+      "description": "The commercial type of a SKU.",
+      "enum": [
+        "consumption",
+        "subscription",
+        "one_time"
+      ],
+      "x-ms-enum": {
+        "name": "SkuType",
+        "modelAsString": true,
+        "values": [
+          {
+            "name": "Consumption",
+            "value": "consumption",
+            "description": "Consumption-based SKU (pay-as-you-go)."
+          },
+          {
+            "name": "Subscription",
+            "value": "subscription",
+            "description": "Subscription-based SKU."
+          },
+          {
+            "name": "OneTime",
+            "value": "one_time",
+            "description": "One-time purchase SKU."
+          }
+        ]
+      }
+    },
+    "Upn": {
+      "type": "object",
+      "description": "UPN (Unified Product Node) resource.\n\nA UPN is a provider-scoped, tenant-level, read-only proxy resource that\nrepresents one transactable value-exchange in the Microsoft commercial\ncatalog. It is addressed at `/providers/Microsoft.Commerce/upns/{upnGuid}`.",
+      "properties": {
+        "properties": {
+          "$ref": "#/definitions/UpnProperties",
+          "description": "The properties of the UPN resource."
+        }
+      },
+      "allOf": [
+        {
+          "$ref": "../../../../../../common-types/resource-management/v6/types.json#/definitions/ProxyResource"
+        }
+      ]
+    },
+    "UpnFragment": {
+      "type": "string",
+      "description": "Fragment names that can be requested via the `fragments` query parameter\non UPN read operations. Each fragment is an opt-in subtree exposed under\n`properties.{fragmentName}` in the response.",
+      "enum": [
+        "listing",
+        "pricing",
+        "purchase",
+        "lifecycle",
+        "display",
+        "tax",
+        "term",
+        "benefits",
+        "bundle",
+        "eligibility",
+        "permutations",
+        "tags",
+        "search",
+        "financial",
+        "externalIds"
+      ],
+      "x-ms-enum": {
+        "name": "UpnFragment",
+        "modelAsString": true,
+        "values": [
+          {
+            "name": "Listing",
+            "value": "listing",
+            "description": "Listing and catalog-presentation fragment."
+          },
+          {
+            "name": "Pricing",
+            "value": "pricing",
+            "description": "List / retail / rate-card pricing fragment (not customer-negotiated pricing)."
+          },
+          {
+            "name": "Purchase",
+            "value": "purchase",
+            "description": "Purchase flow configuration fragment."
+          },
+          {
+            "name": "Lifecycle",
+            "value": "lifecycle",
+            "description": "Lifecycle metadata fragment."
+          },
+          {
+            "name": "Display",
+            "value": "display",
+            "description": "Display metadata fragment."
+          },
+          {
+            "name": "Tax",
+            "value": "tax",
+            "description": "Tax configuration fragment."
+          },
+          {
+            "name": "Term",
+            "value": "term",
+            "description": "Term and billing-plan fragment."
+          },
+          {
+            "name": "Benefits",
+            "value": "benefits",
+            "description": "Benefits fragment."
+          },
+          {
+            "name": "Bundle",
+            "value": "bundle",
+            "description": "Bundle composition fragment."
+          },
+          {
+            "name": "Eligibility",
+            "value": "eligibility",
+            "description": "Eligibility predicates fragment."
+          },
+          {
+            "name": "Permutations",
+            "value": "permutations",
+            "description": "Compact channel/market/salesMotion permutations fragment."
+          },
+          {
+            "name": "Tags",
+            "value": "tags",
+            "description": "Catalog tags fragment."
+          },
+          {
+            "name": "Search",
+            "value": "search",
+            "description": "Search keywords fragment."
+          },
+          {
+            "name": "Financial",
+            "value": "financial",
+            "description": "Financial classification fragment."
+          },
+          {
+            "name": "ExternalIds",
+            "value": "externalIds",
+            "description": "External identifiers fragment."
+          }
+        ]
+      }
+    },
+    "UpnListResult": {
+      "type": "object",
+      "description": "The response of a Upn list operation.",
+      "properties": {
+        "value": {
+          "type": "array",
+          "description": "The Upn items on this page",
+          "items": {
+            "$ref": "#/definitions/Upn"
+          }
+        },
+        "nextLink": {
+          "type": "string",
+          "format": "uri",
+          "description": "The link to the next page of items"
+        }
+      },
+      "required": [
+        "value"
+      ]
+    },
+    "UpnOwnership": {
+      "type": "string",
+      "description": "Ownership classification of a product. Indicates whether the product is\nowned by Microsoft (first-party) or by a third-party publisher.",
+      "enum": [
+        "1PP",
+        "3PP"
+      ],
+      "x-ms-enum": {
+        "name": "UpnOwnership",
+        "modelAsString": true,
+        "values": [
+          {
+            "name": "1PP",
+            "value": "1PP",
+            "description": "First-party (Microsoft-owned) product."
+          },
+          {
+            "name": "3PP",
+            "value": "3PP",
+            "description": "Third-party (publisher-owned) product."
+          }
+        ]
+      }
+    },
+    "UpnProperties": {
+      "type": "object",
+      "description": "Properties of a UPN (Unified Product Node) resource. A UPN is the\ntransactable catalog identity and carries denormalized product and SKU\nsummaries plus the value-exchange identity.",
+      "properties": {
+        "valueExchange": {
+          "$ref": "#/definitions/ValueExchange",
+          "description": "The value-exchange identity that this UPN represents."
+        },
+        "product": {
+          "$ref": "#/definitions/ProductSummary",
+          "description": "Denormalized product summary."
+        },
+        "sku": {
+          "$ref": "#/definitions/SkuSummary",
+          "description": "Denormalized SKU summary."
+        },
+        "template": {
+          "type": "string",
+          "description": "The offer-template identifier for this UPN (for example, \"offer-template/az-vm\")."
+        }
+      },
+      "required": [
+        "valueExchange",
+        "product",
+        "sku"
+      ]
+    },
+    "ValueExchange": {
+      "type": "object",
+      "description": "Value-exchange (UPN identity) metadata. The value exchange is the leaf of\nthe OCP Product -> SKU -> Value Exchange hierarchy and is the transactable\nidentity addressed by this resource.",
+      "properties": {
+        "id": {
+          "type": "string",
+          "description": "The stable identifier of the value exchange."
+        },
+        "unit": {
+          "$ref": "#/definitions/ValueExchangeUnit",
+          "description": "Unit metadata for the value exchange."
+        },
+        "dimensions": {
+          "$ref": "#/definitions/ValueExchangeDimensions",
+          "description": "Dimension metadata for the value exchange."
+        }
+      },
+      "required": [
+        "id"
+      ]
+    },
+    "ValueExchangeDimensions": {
+      "type": "object",
+      "description": "Dimension metadata associated with a value exchange.",
+      "properties": {
+        "location": {
+          "type": "string",
+          "description": "The location dimension (for example, an Azure region)."
+        },
+        "feature": {
+          "type": "string",
+          "description": "The feature dimension (for example, a product feature name)."
+        }
+      }
+    },
+    "ValueExchangeUnit": {
+      "type": "object",
+      "description": "Unit metadata associated with a value exchange.",
+      "properties": {
+        "hint": {
+          "type": "string",
+          "description": "A human-readable hint describing the unit (for example, \"vCPU Duration - 1 Hour\")."
+        }
+      }
+    }
+  },
+  "parameters": {
+    "FragmentsQueryParameter": {
+      "name": "fragments",
+      "in": "query",
+      "description": "A comma-separated list of fragment names to include in the response,\nor `*` to include all fragments. Example: `pricing,permutations,display`.",
+      "required": false,
+      "type": "string",
+      "x-ms-parameter-location": "method"
+    }
+  }
+}
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/readme.md b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/readme.md
new file mode 100644
index 000000000000..2c9930f47938
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/readme.md
@@ -0,0 +1,53 @@
+# Microsoft.Commerce OfferCatalog
+
+> see https://aka.ms/autorest
+
+This is the AutoRest configuration file for the Microsoft.Commerce Offer Catalog service.
+
+---
+
+## Getting Started
+
+To build the SDK for Microsoft.Commerce Offer Catalog, simply [Install AutoRest](https://aka.ms/autorest) and in this folder, run:
+
+> `autorest`
+
+---
+
+## Configuration
+
+### Basic Information
+
+These are the global settings for the Offer Catalog API.
+
+```yaml
+openapi-type: arm
+tag: package-2026-04-24-preview
+```
+
+### Tag: package-2026-04-24-preview
+
+These settings apply only when `--tag=package-2026-04-24-preview` is specified on the command line.
+
+```yaml $(tag) == 'package-2026-04-24-preview'
+input-file:
+  - preview/2026-04-24-preview/offerCatalog.json
+```
+
+---
+
+# Code Generation
+
+## Swagger to SDK
+
+This section describes what SDK should be generated by the automatic system.
+This is not used by Autorest itself.
+
+``` yaml $(swagger-to-sdk)
+swagger-to-sdk:
+  - repo: azure-sdk-for-net
+  - repo: azure-sdk-for-python
+  - repo: azure-sdk-for-java
+  - repo: azure-sdk-for-js
+  - repo: azure-sdk-for-go
+```
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/tspconfig.yaml b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/tspconfig.yaml
new file mode 100644
index 000000000000..d3cf2f7fda90
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/tspconfig.yaml
@@ -0,0 +1,15 @@
+parameters:
+  "service-dir":
+    default: "sdk/commerce"
+emit:
+  - "@azure-tools/typespec-autorest"
+options:
+  "@azure-tools/typespec-autorest":
+    emitter-output-dir: "{project-root}"
+    output-file: "{version-status}/{version}/offerCatalog.json"
+    examples-dir: "{project-root}/examples"
+    arm-types-dir: "{project-root}/../../../../common-types/resource-management"
+    use-read-only-status-schema: true
+linter:
+  extends:
+    - "@azure-tools/typespec-azure-rulesets/resource-manager"
diff --git a/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/upns.tsp b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/upns.tsp
new file mode 100644
index 000000000000..9e83a26b3f96
--- /dev/null
+++ b/specification/commerce/resource-manager/Microsoft.Commerce/OfferCatalog/upns.tsp
@@ -0,0 +1,55 @@
+import "@typespec/http";
+import "@typespec/rest";
+import "@azure-tools/typespec-azure-core";
+import "@azure-tools/typespec-azure-resource-manager";
+import "./models.tsp";
+
+using TypeSpec.Http;
+using TypeSpec.Rest;
+using Azure.Core;
+using Azure.ResourceManager;
+
+namespace Microsoft.Commerce;
+
+/**
+ * UPN (Unified Product Node) resource.
+ *
+ * A UPN is a provider-scoped, tenant-level, read-only proxy resource that
+ * represents one transactable value-exchange in the Microsoft commercial
+ * catalog. It is addressed at `/providers/Microsoft.Commerce/upns/{upnGuid}`.
+ */
+@tenantResource
+model Upn is Azure.ResourceManager.ProxyResource<UpnProperties> {
+  ...ResourceNameParameter<
+    Resource = Upn,
+    KeyName = "upnGuid",
+    SegmentName = "upns",
+    NamePattern = "^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$"
+  >;
+}
+
+/** Read-only operations on UPN catalog resources. */
+@armResourceOperations
+interface Upns {
+  /**
+   * Get a single UPN resource by its GUID identifier. Returns the identity
+   * envelope of the UPN.
+   */
+  get is Extension.Read<Extension.Tenant, Upn>;
+
+  /**
+   * List UPN resources at tenant/provider scope. Returns the identity
+   * envelope for each UPN by default; use the `fragments` query parameter
+   * to opt in to additional fragment subtrees on every listed UPN.
+   */
+  listByTenant is Extension.ListByTarget<
+    Extension.Tenant,
+    Upn,
+    Parameters = FragmentsQueryParameter
+  >;
+}
+
+@@doc(Upn.name,
+  "The GUID identifier of the UPN. Corresponds to the OCP value-exchange productCode."
+);
+@@doc(Upn.properties, "The properties of the UPN resource.");