diff --git a/flagship/dist-deno/src/decision/DecisionManager.ts b/flagship/dist-deno/src/decision/DecisionManager.ts
index 69e49f04..710d9ee8 100644
--- a/flagship/dist-deno/src/decision/DecisionManager.ts
+++ b/flagship/dist-deno/src/decision/DecisionManager.ts
@@ -176,7 +176,11 @@ export abstract class DecisionManager implements IDecisionManager {
       visitor_consent: visitor.hasConsented
     };
 
-    const url = `${this.config.decisionApiUrl || BASE_API_URL}${this.config.envId}${URL_CAMPAIGNS}?${EXPOSE_ALL_KEYS}=true&extras[]=accountSettings`;
+    // When using custom decisionApiUrl, assume it already includes the full path (e.g., /v2/campaigns)
+    // When using default BASE_API_URL, include envId in path for cloud compatibility
+    const url = this.config.decisionApiUrl
+      ? `${this.config.decisionApiUrl}${URL_CAMPAIGNS}?${EXPOSE_ALL_KEYS}=true&extras[]=accountSettings`
+      : `${BASE_API_URL}${this.config.envId}${URL_CAMPAIGNS}?${EXPOSE_ALL_KEYS}=true&extras[]=accountSettings`;
     const now = Date.now();
 
     try {
diff --git a/flagship/src/decision/DecisionManager.ts b/flagship/src/decision/DecisionManager.ts
index f4cad871..52a5c98d 100644
--- a/flagship/src/decision/DecisionManager.ts
+++ b/flagship/src/decision/DecisionManager.ts
@@ -176,7 +176,11 @@ export abstract class DecisionManager implements IDecisionManager {
       visitor_consent: visitor.hasConsented
     };
 
-    const url = `${this.config.decisionApiUrl || BASE_API_URL}${this.config.envId}${URL_CAMPAIGNS}?${EXPOSE_ALL_KEYS}=true&extras[]=accountSettings`;
+    // When using custom decisionApiUrl, assume it already includes the full path (e.g., /v2/campaigns)
+    // When using default BASE_API_URL, include envId in path for cloud compatibility
+    const url = this.config.decisionApiUrl
+      ? `${this.config.decisionApiUrl}${URL_CAMPAIGNS}?${EXPOSE_ALL_KEYS}=true&extras[]=accountSettings`
+      : `${BASE_API_URL}${this.config.envId}${URL_CAMPAIGNS}?${EXPOSE_ALL_KEYS}=true&extras[]=accountSettings`;
     const now = Date.now();
 
     try {