diff --git a/.changeset/fix-update-env-var-name-scope.md b/.changeset/fix-update-env-var-name-scope.md
new file mode 100644
index 00000000000..0f64bc5ba2f
--- /dev/null
+++ b/.changeset/fix-update-env-var-name-scope.md
@@ -0,0 +1,5 @@
+---
+"@trigger.dev/sdk": patch
+---
+
+Fix `updateEnvVar` incorrectly reading from an out-of-scope variable when called with the `(projectRef, slug, name, params)` overload. The `name` parameter was undefined in the implementation body; it now correctly reads from `nameOrRequestOptions`.
diff --git a/packages/trigger-sdk/src/v3/envvars.ts b/packages/trigger-sdk/src/v3/envvars.ts
index 153be22a3d3..82cd0c49c47 100644
--- a/packages/trigger-sdk/src/v3/envvars.ts
+++ b/packages/trigger-sdk/src/v3/envvars.ts
@@ -338,7 +338,7 @@ export function update(
 
     $projectRef = projectRefOrName;
     $slug = slugOrParams;
-    $name = name!;
+    $name = nameOrRequestOptions as string;
     $params = params;
   }