diff --git a/ui/app/templates/jobs/job/task-group.hbs b/ui/app/templates/jobs/job/task-group.hbs
index 7910b1059..307cd2bbf 100644
--- a/ui/app/templates/jobs/job/task-group.hbs
+++ b/ui/app/templates/jobs/job/task-group.hbs
@@ -11,6 +11,7 @@
       <Exec::OpenButton @job={{model.job}} @taskGroup={{model}} />
       {{#if model.scaling}}
       <StepperInput
+        data-test-task-group-count-stepper
         @min={{model.scaling.min}}
         @max={{model.scaling.max}}
         @value={{model.count}}
diff --git a/ui/tests/acceptance/task-group-detail-test.js b/ui/tests/acceptance/task-group-detail-test.js
index 8b7761526..15b477b34 100644
--- a/ui/tests/acceptance/task-group-detail-test.js
+++ b/ui/tests/acceptance/task-group-detail-test.js
@@ -1,4 +1,4 @@
-import { currentURL } from '@ember/test-helpers';
+import { currentURL, settled } from '@ember/test-helpers';
 import { module, test } from 'qunit';
 import { setupApplicationTest } from 'ember-qunit';
 import { setupMirage } from 'ember-cli-mirage/test-support';
@@ -11,6 +11,7 @@ let job;
 let taskGroup;
 let tasks;
 let allocations;
+let managementToken;
 
 const sum = (total, n) => total + n;
 
@@ -61,6 +62,8 @@ module('Acceptance | task group detail', function(hooks) {
       previousAllocation: allocations[0].id,
     });
 
+    managementToken = server.create('token');
+
     window.localStorage.clear();
   });
 
@@ -297,6 +300,59 @@ module('Acceptance | task group detail', function(hooks) {
     });
   });
 
+  test('the count stepper sends the appropriate POST request', async function(assert) {
+    window.localStorage.nomadTokenSecret = managementToken.secretId;
+
+    job = server.create('job', {
+      groupCount: 0,
+      createAllocations: false,
+      shallow: true,
+      noActiveDeployment: true,
+    });
+    const scalingGroup = server.create('task-group', {
+      job,
+      name: 'scaling',
+      count: 1,
+      shallow: true,
+      withScaling: true,
+    });
+    job.update({ taskGroupIds: [scalingGroup.id] });
+
+    await TaskGroup.visit({ id: job.id, name: scalingGroup.name });
+    await TaskGroup.countStepper.increment.click();
+    await settled();
+
+    const scaleRequest = server.pretender.handledRequests.find(req => req.url.endsWith('/scale'));
+    const requestBody = JSON.parse(scaleRequest.requestBody);
+    assert.equal(requestBody.Target.Group, scalingGroup.name);
+    assert.equal(requestBody.Count, scalingGroup.count + 1);
+  });
+
+  test('the count stepper is disabled when a deployment is running', async function(assert) {
+    window.localStorage.nomadTokenSecret = managementToken.secretId;
+
+    job = server.create('job', {
+      groupCount: 0,
+      createAllocations: false,
+      shallow: true,
+      activeDeployment: true,
+    });
+    const scalingGroup = server.create('task-group', {
+      job,
+      name: 'scaling',
+      count: 1,
+      shallow: true,
+      withScaling: true,
+    });
+    job.update({ taskGroupIds: [scalingGroup.id] });
+
+    await TaskGroup.visit({ id: job.id, name: scalingGroup.name });
+
+    assert.ok(TaskGroup.countStepper.input.isDisabled);
+    assert.ok(TaskGroup.countStepper.increment.isDisabled);
+    assert.ok(TaskGroup.countStepper.decrement.isDisabled);
+  });
+
   test('when the job for the task group is not found, an error message is shown, but the URL persists', async function(assert) {
     await TaskGroup.visit({ id: 'not-a-real-job', name: 'not-a-real-task-group' });
 
diff --git a/ui/tests/pages/components/stepper-input.js b/ui/tests/pages/components/stepper-input.js
index 807b6cf95..0fec7c85e 100644
--- a/ui/tests/pages/components/stepper-input.js
+++ b/ui/tests/pages/components/stepper-input.js
@@ -24,6 +24,7 @@ export default scope => ({
     blur: blurrable(),
     value: value(),
     esc: triggerable('keydown', '', { eventProperties: { keyCode: 27 } }),
+    isDisabled: attribute('disabled'),
   },
 
   decrement: {
diff --git a/ui/tests/pages/jobs/job/task-group.js b/ui/tests/pages/jobs/job/task-group.js
index 19f120f1f..d69b26750 100644
--- a/ui/tests/pages/jobs/job/task-group.js
+++ b/ui/tests/pages/jobs/job/task-group.js
@@ -12,6 +12,7 @@ import {
 import allocations from 'nomad-ui/tests/pages/components/allocations';
 import error from 'nomad-ui/tests/pages/components/error';
 import pageSizeSelect from 'nomad-ui/tests/pages/components/page-size-select';
+import stepperInput from 'nomad-ui/tests/pages/components/stepper-input';
 import LifecycleChart from 'nomad-ui/tests/pages/components/lifecycle-chart';
 
 export default create({
@@ -21,6 +22,8 @@ export default create({
 
   search: fillable('.search-box input'),
 
+  countStepper: stepperInput('[data-test-task-group-count-stepper]'),
+
   tasksCount: text('[data-test-task-group-tasks]'),
   cpu: text('[data-test-task-group-cpu]'),
   mem: text('[data-test-task-group-mem]'),