diff --git a/sdk/resourcemanager/Azure.ResourceManager.Core/src/ArmClient.cs b/sdk/resourcemanager/Azure.ResourceManager.Core/src/ArmClient.cs
index d695e8c05035..bd43c37100e6 100644
--- a/sdk/resourcemanager/Azure.ResourceManager.Core/src/ArmClient.cs
+++ b/sdk/resourcemanager/Azure.ResourceManager.Core/src/ArmClient.cs
@@ -90,7 +90,7 @@ private ArmClient(
                 throw new ArgumentNullException(nameof(credential));
 
             Credential = credential;
-            BaseUri = baseUri;
+            BaseUri = baseUri ?? new Uri(DefaultUri);
             ClientOptions = options?.Clone() ?? new ArmClientOptions();
             Pipeline = ManagementPipelineBuilder.Build(Credential, BaseUri, ClientOptions);