diff --git a/app/javascript/dashboard/components-next/sidebar/Sidebar.vue b/app/javascript/dashboard/components-next/sidebar/Sidebar.vue
index d9f523dfc..f71652ca0 100644
--- a/app/javascript/dashboard/components-next/sidebar/Sidebar.vue
+++ b/app/javascript/dashboard/components-next/sidebar/Sidebar.vue
@@ -175,6 +175,9 @@ useEventListener(document, 'touchend', onResizeEnd);
 
 const inboxes = useMapGetter('inboxes/getInboxes');
 const labels = useMapGetter('labels/getLabelsOnSidebar');
+const allUnreadCount = useMapGetter(
+  'conversationUnreadCounts/getAllUnreadCount'
+);
 const getInboxUnreadCount = useMapGetter(
   'conversationUnreadCounts/getInboxUnreadCount'
 );
@@ -297,6 +300,7 @@ const menuItems = computed(() => {
         {
           name: 'All',
           label: t('SIDEBAR.ALL_CONVERSATIONS'),
+          badgeCount: allUnreadCount.value,
           activeOn: ['inbox_conversation'],
           to: accountScopedRoute('home'),
         },
diff --git a/app/javascript/dashboard/store/modules/conversationUnreadCounts.js b/app/javascript/dashboard/store/modules/conversationUnreadCounts.js
index 0503c0806..c03249311 100644
--- a/app/javascript/dashboard/store/modules/conversationUnreadCounts.js
+++ b/app/javascript/dashboard/store/modules/conversationUnreadCounts.js
@@ -2,15 +2,21 @@ import ConversationAPI from '../../api/conversations';
 import types from '../mutation-types';
 
 export const state = {
+  allCount: 0,
   inboxes: {},
   labels: {},
   teams: {},
 };
 
+const normalizeCount = count => {
+  const parsedCount = Number(count);
+  return Number.isFinite(parsedCount) && parsedCount > 0 ? parsedCount : 0;
+};
+
 const normalizeCounts = counts => {
   return Object.entries(counts || {}).reduce((result, [id, count]) => {
-    const parsedCount = Number(count);
-    if (Number.isFinite(parsedCount) && parsedCount > 0) {
+    const parsedCount = normalizeCount(count);
+    if (parsedCount > 0) {
       result[String(id)] = parsedCount;
     }
 
@@ -19,6 +25,9 @@ const normalizeCounts = counts => {
 };
 
 export const getters = {
+  getAllUnreadCount($state) {
+    return $state.allCount;
+  },
   getInboxUnreadCount: $state => inboxId => {
     return $state.inboxes[String(inboxId)] || 0;
   },
@@ -55,6 +64,7 @@ export const actions = {
 
 export const mutations = {
   [types.SET_CONVERSATION_UNREAD_COUNTS]($state, payload = {}) {
+    $state.allCount = normalizeCount(payload.all_count);
     $state.inboxes = normalizeCounts(payload.inboxes);
     $state.labels = normalizeCounts(payload.labels);
     $state.teams = normalizeCounts(payload.teams);
diff --git a/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/actions.spec.js b/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/actions.spec.js
index 3100cdd10..29fadc897 100644
--- a/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/actions.spec.js
+++ b/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/actions.spec.js
@@ -15,6 +15,7 @@ describe('#actions', () => {
   describe('#get', () => {
     it('commits unread counts when API is successful', async () => {
       const payload = {
+        all_count: 2,
         inboxes: { 1: '2' },
         labels: { 3: 4 },
         teams: { 5: 6 },
diff --git a/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/getters.spec.js b/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/getters.spec.js
index a3e74fc37..9fe19e22d 100644
--- a/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/getters.spec.js
+++ b/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/getters.spec.js
@@ -3,6 +3,7 @@ import { getters } from '../../conversationUnreadCounts';
 describe('#getters', () => {
   it('returns inbox unread count by id', () => {
     const state = {
+      allCount: 0,
       inboxes: { 1: 2 },
       labels: {},
       teams: {},
@@ -15,6 +16,7 @@ describe('#getters', () => {
 
   it('returns label unread count by id', () => {
     const state = {
+      allCount: 0,
       inboxes: {},
       labels: { 3: 4 },
       teams: {},
@@ -27,6 +29,7 @@ describe('#getters', () => {
 
   it('returns team unread count by id', () => {
     const state = {
+      allCount: 0,
       inboxes: {},
       labels: {},
       teams: { 5: 6 },
@@ -37,8 +40,20 @@ describe('#getters', () => {
     expect(getters.getTeamUnreadCount(state)(6)).toBe(0);
   });
 
+  it('returns all unread count', () => {
+    const state = {
+      allCount: 7,
+      inboxes: {},
+      labels: {},
+      teams: {},
+    };
+
+    expect(getters.getAllUnreadCount(state)).toBe(7);
+  });
+
   it('returns unread count maps', () => {
     const state = {
+      allCount: 0,
       inboxes: { 1: 2 },
       labels: { 3: 4 },
       teams: { 5: 6 },
diff --git a/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/mutations.spec.js b/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/mutations.spec.js
index 3f7e2b1ec..8941d7430 100644
--- a/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/mutations.spec.js
+++ b/app/javascript/dashboard/store/modules/specs/conversationUnreadCounts/mutations.spec.js
@@ -4,9 +4,10 @@ import { mutations } from '../../conversationUnreadCounts';
 describe('#mutations', () => {
   describe('#SET_CONVERSATION_UNREAD_COUNTS', () => {
     it('normalizes unread count payload', () => {
-      const state = { inboxes: {}, labels: {}, teams: {} };
+      const state = { allCount: 0, inboxes: {}, labels: {}, teams: {} };
 
       mutations[types.SET_CONVERSATION_UNREAD_COUNTS](state, {
+        all_count: '3',
         inboxes: {
           1: '2',
           2: 0,
@@ -23,6 +24,7 @@ describe('#mutations', () => {
       });
 
       expect(state).toEqual({
+        allCount: 3,
         inboxes: { 1: 2 },
         labels: { 4: 5 },
         teams: { 6: 7 },
@@ -31,6 +33,7 @@ describe('#mutations', () => {
 
     it('clears counts when payload is empty', () => {
       const state = {
+        allCount: 2,
         inboxes: { 1: 2 },
         labels: { 4: 5 },
         teams: { 6: 7 },
@@ -39,10 +42,21 @@ describe('#mutations', () => {
       mutations[types.SET_CONVERSATION_UNREAD_COUNTS](state, {});
 
       expect(state).toEqual({
+        allCount: 0,
         inboxes: {},
         labels: {},
         teams: {},
       });
     });
+
+    it('normalizes invalid aggregate counts to zero', () => {
+      const state = { allCount: 2, inboxes: {}, labels: {}, teams: {} };
+
+      mutations[types.SET_CONVERSATION_UNREAD_COUNTS](state, {
+        all_count: 'invalid',
+      });
+
+      expect(state.allCount).toBe(0);
+    });
   });
 });
diff --git a/app/services/conversations/unread_counts/counter.rb b/app/services/conversations/unread_counts/counter.rb
index f4126b61f..b1ba5ddb0 100644
--- a/app/services/conversations/unread_counts/counter.rb
+++ b/app/services/conversations/unread_counts/counter.rb
@@ -19,8 +19,11 @@ class Conversations::UnreadCounts::Counter
     ensure_base_cache!
     ensure_assignment_cache! if assignment_mode?
 
+    inbox_counts = unread_inbox_counts
+
     {
-      inboxes: unread_inbox_counts,
+      all_count: inbox_counts.values.sum,
+      inboxes: inbox_counts,
       labels: unread_label_counts,
       teams: unread_team_counts
     }
@@ -191,7 +194,7 @@ class Conversations::UnreadCounts::Counter
   end
 
   def empty_counts
-    { inboxes: {}, labels: {}, teams: {} }
+    { all_count: 0, inboxes: {}, labels: {}, teams: {} }
   end
 
   def store
diff --git a/spec/controllers/api/v1/accounts/conversations_controller_spec.rb b/spec/controllers/api/v1/accounts/conversations_controller_spec.rb
index f8fd446d2..bdb8117ac 100644
--- a/spec/controllers/api/v1/accounts/conversations_controller_spec.rb
+++ b/spec/controllers/api/v1/accounts/conversations_controller_spec.rb
@@ -141,6 +141,7 @@ RSpec.describe 'Conversations API', type: :request do
 
           expect(response).to have_http_status(:success)
           expect(response.parsed_body['payload']).to eq(
+            'all_count' => 1,
             'inboxes' => { visible_inbox.id.to_s => 1 },
             'labels' => { label.id.to_s => 1 },
             'teams' => {}
diff --git a/spec/enterprise/services/conversations/unread_counts/counter_spec.rb b/spec/enterprise/services/conversations/unread_counts/counter_spec.rb
index cbb2d6c98..e8f850e78 100644
--- a/spec/enterprise/services/conversations/unread_counts/counter_spec.rb
+++ b/spec/enterprise/services/conversations/unread_counts/counter_spec.rb
@@ -26,6 +26,7 @@ RSpec.describe Conversations::UnreadCounts::Counter do
 
     result = described_class.new(account: account, user: agent).perform
 
+    expect(result[:all_count]).to eq(2)
     expect(result[:inboxes]).to eq(inbox.id.to_s => 2)
     expect(result[:labels]).to eq(label.id.to_s => 2)
     expect(result[:teams]).to eq(team.id.to_s => 2)
@@ -40,6 +41,7 @@ RSpec.describe Conversations::UnreadCounts::Counter do
 
     result = described_class.new(account: account, user: agent).perform
 
+    expect(result[:all_count]).to eq(2)
     expect(result[:inboxes]).to eq(inbox.id.to_s => 2)
     expect(result[:labels]).to eq(label.id.to_s => 2)
     expect(result[:teams]).to eq(team.id.to_s => 2)
@@ -53,6 +55,7 @@ RSpec.describe Conversations::UnreadCounts::Counter do
 
     result = described_class.new(account: account, user: agent).perform
 
+    expect(result[:all_count]).to eq(1)
     expect(result[:inboxes]).to eq(inbox.id.to_s => 1)
     expect(result[:labels]).to eq(label.id.to_s => 1)
     expect(result[:teams]).to eq(team.id.to_s => 1)
@@ -65,7 +68,7 @@ RSpec.describe Conversations::UnreadCounts::Counter do
 
     result = described_class.new(account: account, user: agent).perform
 
-    expect(result).to eq(inboxes: {}, labels: {}, teams: {})
+    expect(result).to eq(all_count: 0, inboxes: {}, labels: {}, teams: {})
     expect(store.base_ready?(account.id)).to be(false)
     expect(store.assignment_ready?(account.id)).to be(false)
   end
diff --git a/spec/services/conversations/unread_counts/counter_spec.rb b/spec/services/conversations/unread_counts/counter_spec.rb
index bfd10436e..723f2d437 100644
--- a/spec/services/conversations/unread_counts/counter_spec.rb
+++ b/spec/services/conversations/unread_counts/counter_spec.rb
@@ -62,6 +62,7 @@ RSpec.describe Conversations::UnreadCounts::Counter do
     result = described_class.new(account: account, user: agent).perform
 
     expect(result).to eq(
+      all_count: 1,
       inboxes: { visible_inbox.id.to_s => 1 },
       labels: { label.id.to_s => 1 },
       teams: { visible_team.id.to_s => 1 }
@@ -75,6 +76,7 @@ RSpec.describe Conversations::UnreadCounts::Counter do
     result = described_class.new(account: account, user: admin).perform
 
     expect(result).to eq(
+      all_count: 2,
       inboxes: { visible_inbox.id.to_s => 1, hidden_inbox.id.to_s => 1 },
       labels: { label.id.to_s => 2 },
       teams: { visible_team.id.to_s => 2 }
@@ -87,6 +89,7 @@ RSpec.describe Conversations::UnreadCounts::Counter do
     result = described_class.new(account: account, user: agent).perform
 
     expect(result).to eq(
+      all_count: 1,
       inboxes: { visible_inbox.id.to_s => 1 },
       labels: {},
       teams: { visible_team.id.to_s => 1 }