diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 35c30ad..81d2de2 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "1.30.0"
+  ".": "1.31.0"
 }
\ No newline at end of file
diff --git a/.stats.yml b/.stats.yml
index 320998e..f2277cf 100644
--- a/.stats.yml
+++ b/.stats.yml
@@ -1,4 +1,4 @@
 configured_endpoints: 118
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/orb%2Forb-828c91953d2351040fdd4d90a3d9eafd09f9d240c4f6ce0441b7a10c06c1c722.yml
-openapi_spec_hash: c82bc88563f80f600e59e22014d4cec4
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/orb%2Forb-cbce25283cb9c3282e03e08b7ee81395436af7d0eb480ffcbab307b5bf1c92a0.yml
+openapi_spec_hash: c286edf46db95dee05eb6f180ac24ab0
 config_hash: 1f73a949b649ecfe6ec68ba1bb459dc2
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 648a3aa..90734c4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## 1.31.0 (2025-10-23)
+
+Full Changelog: [v1.30.0...v1.31.0](https://github.com/orbcorp/orb-go/compare/v1.30.0...v1.31.0)
+
+### Features
+
+* **api:** api update ([021e262](https://github.com/orbcorp/orb-go/commit/021e262bf67cf8b3244d6e3a26776f72226c0e07))
+
 ## 1.30.0 (2025-10-17)
 
 Full Changelog: [v1.29.0...v1.30.0](https://github.com/orbcorp/orb-go/compare/v1.29.0...v1.30.0)
diff --git a/README.md b/README.md
index 88782ba..9328866 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ Or to pin the version:
 <!-- x-release-please-start-version -->
 
 ```sh
-go get -u 'github.com/orbcorp/orb-go@v1.30.0'
+go get -u 'github.com/orbcorp/orb-go@v1.31.0'
 ```
 
 <!-- x-release-please-end -->
diff --git a/internal/version.go b/internal/version.go
index c629232..b7047d5 100644
--- a/internal/version.go
+++ b/internal/version.go
@@ -2,4 +2,4 @@
 
 package internal
 
-const PackageVersion = "1.30.0" // x-release-please-version
+const PackageVersion = "1.31.0" // x-release-please-version
diff --git a/subscriptionchange.go b/subscriptionchange.go
index 68e96f6..de8d11e 100644
--- a/subscriptionchange.go
+++ b/subscriptionchange.go
@@ -519,6 +519,14 @@ type SubscriptionChangeApplyParams struct {
 	// Mark all pending invoices that are payable as paid. If amount is also provided,
 	// mark as paid and credit the difference to the customer's balance.
 	MarkAsPaid param.Field[bool] `json:"mark_as_paid"`
+	// An optional external ID to associate with the payment. Only applicable when
+	// mark_as_paid is true.
+	PaymentExternalID param.Field[string] `json:"payment_external_id"`
+	// Optional notes about the payment. Only applicable when mark_as_paid is true.
+	PaymentNotes param.Field[string] `json:"payment_notes"`
+	// A date string to specify the date the payment was received. Only applicable when
+	// mark_as_paid is true. If not provided, defaults to the current date.
+	PaymentReceivedDate param.Field[time.Time] `json:"payment_received_date" format:"date"`
 	// Amount already collected to apply to the customer's balance. If mark_as_paid is
 	// also provided, credit the difference to the customer's balance.
 	PreviouslyCollectedAmount param.Field[string] `json:"previously_collected_amount"`
diff --git a/subscriptionchange_test.go b/subscriptionchange_test.go
index 890cd34..e63931c 100644
--- a/subscriptionchange_test.go
+++ b/subscriptionchange_test.go
@@ -7,6 +7,7 @@ import (
 	"errors"
 	"os"
 	"testing"
+	"time"
 
 	"github.com/orbcorp/orb-go"
 	"github.com/orbcorp/orb-go/internal/testutil"
@@ -53,6 +54,9 @@ func TestSubscriptionChangeApplyWithOptionalParams(t *testing.T) {
 		orb.SubscriptionChangeApplyParams{
 			Description:               orb.F("description"),
 			MarkAsPaid:                orb.F(true),
+			PaymentExternalID:         orb.F("payment_external_id"),
+			PaymentNotes:              orb.F("payment_notes"),
+			PaymentReceivedDate:       orb.F(time.Now()),
 			PreviouslyCollectedAmount: orb.F("previously_collected_amount"),
 		},
 	)