diff --git a/packages/core/src/pool/index.ts b/packages/core/src/pool/index.ts
index 681101e8e..500805d0d 100644
--- a/packages/core/src/pool/index.ts
+++ b/packages/core/src/pool/index.ts
@@ -246,7 +246,7 @@ export const createPool = async ({
               options: {
                 entryInfo,
                 context: {
-                  workerId: index + 1,
+                  taskId: index + 1,
                   project: projectName,
                   rootPath: context.rootPath,
                   projectRoot: project.rootPath,
@@ -323,7 +323,7 @@ export const createPool = async ({
               options: {
                 entryInfo,
                 context: {
-                  workerId: index + 1,
+                  taskId: index + 1,
                   project: projectName,
                   rootPath: context.rootPath,
                   projectRoot: project.rootPath,
diff --git a/packages/core/src/runtime/worker/index.ts b/packages/core/src/runtime/worker/index.ts
index 9dd659ad4..9d1a8624e 100644
--- a/packages/core/src/runtime/worker/index.ts
+++ b/packages/core/src/runtime/worker/index.ts
@@ -58,7 +58,10 @@ const preparePool = async ({
   setRealTimers();
   context.runtimeConfig = undoSerializableConfig(context.runtimeConfig);
 
-  process.env.RSTEST_WORKER_ID = String(context.workerId);
+  // Prefer public env var from tinypool, fallback to context.taskId
+  process.env.RSTEST_WORKER_ID = String(
+    process.__tinypool_state__.workerId || context.taskId,
+  );
 
   const cleanupFns: (() => MaybePromise<void>)[] = [];
 
diff --git a/packages/core/src/types/worker.ts b/packages/core/src/types/worker.ts
index 9e2ea471a..0b5eac0df 100644
--- a/packages/core/src/types/worker.ts
+++ b/packages/core/src/types/worker.ts
@@ -55,7 +55,7 @@ export type WorkerContext = {
   projectRoot: ProjectContext['rootPath'];
   project: string;
   runtimeConfig: RuntimeConfig;
-  workerId: number;
+  taskId: number;
 };
 
 export type RunWorkerOptions = {