diff --git a/bin/testObservability/helper/helper.js b/bin/testObservability/helper/helper.js
index 434d4a42..ad9c56ba 100644
--- a/bin/testObservability/helper/helper.js
+++ b/bin/testObservability/helper/helper.js
@@ -92,8 +92,16 @@ const supportFileCleanup = () => {
 
 exports.buildStopped = false;
 
+const isValidTestHubValue = (value) => !!value && value !== "null" && value !== "undefined";
+
+// A build started at TestHub for any product (e.g. accessibility with observability off)
+// must also be stopped at TestHub, otherwise TestHub never finalises it downstream.
+exports.isTestHubBuildLaunched = () => {
+  return isValidTestHubValue(process.env.BROWSERSTACK_TESTHUB_UUID) && isValidTestHubValue(process.env.BROWSERSTACK_TESTHUB_JWT);
+}
+
 exports.printBuildLink = async (shouldStopSession, exitCode = null) => {
-  if(!this.isTestObservabilitySession()) return;
+  if(!this.isTestObservabilitySession() && !this.isTestHubBuildLaunched()) return;
   // SDK-6211: the build-stop may be sent early (runs.js fires it at poll-resolution, before the
   // post-test 5s wait + artifact download + report generation, so builds_th.finished_at — which
   // the collector stamps at stop-event receipt — reflects the test window rather than the full CLI
@@ -677,8 +685,11 @@ exports.shouldReRunObservabilityTests = () => {
 }
 
 exports.stopBuildUpstream = async () => {
-  if (process.env.BS_TESTOPS_BUILD_COMPLETED === "true") {
-    if(process.env.BS_TESTOPS_JWT == "null" || process.env.BS_TESTOPS_BUILD_HASHED_ID == "null") {
+  const observabilityBuildLaunched = process.env.BS_TESTOPS_BUILD_COMPLETED === "true";
+  if (observabilityBuildLaunched || exports.isTestHubBuildLaunched()) {
+    const jwt = observabilityBuildLaunched ? process.env.BS_TESTOPS_JWT : process.env.BROWSERSTACK_TESTHUB_JWT;
+    const buildHashedId = observabilityBuildLaunched ? process.env.BS_TESTOPS_BUILD_HASHED_ID : process.env.BROWSERSTACK_TESTHUB_UUID;
+    if(!isValidTestHubValue(jwt) || !isValidTestHubValue(buildHashedId)) {
       exports.debug(`EXCEPTION IN stopBuildUpstream REQUEST TO ${TEST_REPORTING_ANALYTICS} : Missing authentication token`);
       return {
         status: 'error',
@@ -692,14 +703,14 @@ exports.stopBuildUpstream = async () => {
       };
       const config = {
         headers: {
-          'Authorization': `Bearer ${process.env.BS_TESTOPS_JWT}`,
+          'Authorization': `Bearer ${jwt}`,
           'Content-Type': 'application/json',
           'X-BSTACK-TESTOPS': 'true'
         }
       };
 
       try {
-        const response = await exports.nodeRequest('PUT',`api/v1/builds/${process.env.BS_TESTOPS_BUILD_HASHED_ID}/stop`,data,config);
+        const response = await exports.nodeRequest('PUT',`api/v1/builds/${buildHashedId}/stop`,data,config);
         if(response.data && response.data.error) {
           throw({message: response.data.error});
         } else {
diff --git a/test/unit/bin/testObservability/buildStop.js b/test/unit/bin/testObservability/buildStop.js
new file mode 100644
index 00000000..b8089a94
--- /dev/null
+++ b/test/unit/bin/testObservability/buildStop.js
@@ -0,0 +1,88 @@
+'use strict';
+const chai = require('chai');
+const expect = chai.expect;
+const sinon = require('sinon');
+
+const helper = require('../../../../bin/testObservability/helper/helper');
+
+const ENV_KEYS = [
+  'BROWSERSTACK_TEST_OBSERVABILITY',
+  'BS_TESTOPS_BUILD_COMPLETED',
+  'BS_TESTOPS_JWT',
+  'BS_TESTOPS_BUILD_HASHED_ID',
+  'BROWSERSTACK_TESTHUB_UUID',
+  'BROWSERSTACK_TESTHUB_JWT',
+];
+
+describe('TestHub build stop', () => {
+  let savedEnv, nodeRequest;
+
+  beforeEach(() => {
+    savedEnv = {};
+    ENV_KEYS.forEach((k) => { savedEnv[k] = process.env[k]; delete process.env[k]; });
+    helper.buildStopped = false;
+    nodeRequest = sinon.stub(helper, 'nodeRequest').resolves({ data: {} });
+  });
+
+  afterEach(() => {
+    sinon.restore();
+    ENV_KEYS.forEach((k) => {
+      if (savedEnv[k] === undefined) delete process.env[k]; else process.env[k] = savedEnv[k];
+    });
+    helper.buildStopped = false;
+  });
+
+  const stopCall = () => nodeRequest.getCalls().find((c) => c.args[0] === 'PUT');
+
+  it('stops an accessibility-only TestHub build when observability is off', async () => {
+    process.env.BROWSERSTACK_TEST_OBSERVABILITY = 'false';
+    process.env.BS_TESTOPS_BUILD_COMPLETED = 'false';
+    process.env.BS_TESTOPS_JWT = 'null';
+    process.env.BS_TESTOPS_BUILD_HASHED_ID = 'null';
+    process.env.BROWSERSTACK_TESTHUB_UUID = 'th-build-uuid';
+    process.env.BROWSERSTACK_TESTHUB_JWT = 'th-jwt';
+
+    await helper.printBuildLink(true);
+
+    const call = stopCall();
+    expect(call, 'PUT stop request').to.exist;
+    expect(call.args[1]).to.equal('api/v1/builds/th-build-uuid/stop');
+    expect(call.args[3].headers.Authorization).to.equal('Bearer th-jwt');
+  });
+
+  it('keeps using the observability token and build id when observability launched the build', async () => {
+    process.env.BROWSERSTACK_TEST_OBSERVABILITY = 'true';
+    process.env.BS_TESTOPS_BUILD_COMPLETED = 'true';
+    process.env.BS_TESTOPS_JWT = 'o11y-jwt';
+    process.env.BS_TESTOPS_BUILD_HASHED_ID = 'o11y-build';
+    process.env.BROWSERSTACK_TESTHUB_UUID = 'o11y-build';
+    process.env.BROWSERSTACK_TESTHUB_JWT = 'o11y-jwt';
+
+    await helper.printBuildLink(true);
+
+    const call = stopCall();
+    expect(call.args[1]).to.equal('api/v1/builds/o11y-build/stop');
+    expect(call.args[3].headers.Authorization).to.equal('Bearer o11y-jwt');
+  });
+
+  it('sends no stop when no TestHub build was launched', async () => {
+    process.env.BROWSERSTACK_TEST_OBSERVABILITY = 'false';
+    process.env.BROWSERSTACK_TESTHUB_UUID = 'null';
+    process.env.BROWSERSTACK_TESTHUB_JWT = 'null';
+
+    await helper.printBuildLink(true);
+
+    expect(stopCall()).to.be.undefined;
+  });
+
+  it('sends the stop only once across repeated calls', async () => {
+    process.env.BROWSERSTACK_TEST_OBSERVABILITY = 'false';
+    process.env.BROWSERSTACK_TESTHUB_UUID = 'th-build-uuid';
+    process.env.BROWSERSTACK_TESTHUB_JWT = 'th-jwt';
+
+    await helper.printBuildLink(true);
+    await helper.printBuildLink(true);
+
+    expect(nodeRequest.getCalls().filter((c) => c.args[0] === 'PUT')).to.have.length(1);
+  });
+});