diff --git a/app/views/shared/milestones/_issuables.html.haml b/app/views/shared/milestones/_issuables.html.haml
index 15ff5b8a27e950217fc4b28c30657353a9b6034e..c8fd45c431998558683b744d2d18b27deee3ad74 100644
--- a/app/views/shared/milestones/_issuables.html.haml
+++ b/app/views/shared/milestones/_issuables.html.haml
@@ -9,6 +9,7 @@
     - if show_counter
       .right
         = issuables.size
+      .pull-right= number_with_delimiter(issuables.size)
 
   - class_prefix = dom_class(issuables).pluralize
   %ul{ class: "well-list #{class_prefix}-sortable-list", id: "#{class_prefix}-list-#{id}", "data-state" => id }
diff --git a/changelogs/unreleased/25277-milestone-counter-number-with-delimiter.yml b/changelogs/unreleased/25277-milestone-counter-number-with-delimiter.yml
new file mode 100644
index 0000000000000000000000000000000000000000..0c9853de3b6ee09ec061e126007bdb91c7f04d77
--- /dev/null
+++ b/changelogs/unreleased/25277-milestone-counter-number-with-delimiter.yml
@@ -0,0 +1,4 @@
+---
+title: Added number_with_delimiter to counter on milestone panels
+merge_request: 
+author: Ryan Harris
diff --git a/spec/views/shared/milestones/_issuables.html.haml.rb b/spec/views/shared/milestones/_issuables.html.haml.rb
new file mode 100644
index 0000000000000000000000000000000000000000..4769d569548840cd2e55fcf9e3b52ff26632bdff
--- /dev/null
+++ b/spec/views/shared/milestones/_issuables.html.haml.rb
@@ -0,0 +1,32 @@
+require 'spec_helper'
+
+describe 'shared/milestones/_issuables.html.haml' do
+  let(:issuables_size) { 100 }
+
+  before do
+    allow(view).to receive_messages(title: nil, id: nil, show_project_name: nil,
+                                    show_full_project_name: nil, dom_class: '',
+                                    issuables: double(size: issuables_size).as_null_object)
+
+    stub_template 'shared/milestones/_issuable.html.haml' => ''
+  end
+
+  it 'should show the issuables count if show_counter is true' do
+    render 'shared/milestones/issuables', show_counter: true
+    expect(rendered).to have_content('100')
+  end
+
+  it 'should not show the issuables count if show_counter is false' do
+    render 'shared/milestones/issuables', show_counter: false
+    expect(rendered).not_to have_content('100')
+  end
+
+  describe 'a high issuables count' do
+    let(:issuables_size) { 1000 }
+
+    it 'should show a delimited number if show_counter is true' do
+      render 'shared/milestones/issuables', show_counter: true
+      expect(rendered).to have_content('1,000')
+    end
+  end
+end