diff --git a/src/lib/ThumbnailsSidebar.js b/src/lib/ThumbnailsSidebar.js
index 7f1b61dd5..b3902a820 100644
--- a/src/lib/ThumbnailsSidebar.js
+++ b/src/lib/ThumbnailsSidebar.js
@@ -254,6 +254,7 @@ class ThumbnailsSidebar {
 
         if (pageNum === this.currentPage) {
             thumbnailEl.classList.add(CLASS_BOX_PREVIEW_THUMBNAIL_IS_SELECTED);
+            thumbnailEl.setAttribute('aria-current', true);
         }
 
         // If image is already in cache, then use it instead of waiting for
@@ -439,8 +440,10 @@ class ThumbnailsSidebar {
             const parsedPageNum = parseInt(thumbnailEl.dataset.bpPageNum, 10);
             if (parsedPageNum === this.currentPage) {
                 thumbnailEl.classList.add(CLASS_BOX_PREVIEW_THUMBNAIL_IS_SELECTED);
+                thumbnailEl.setAttribute('aria-current', true);
             } else {
                 thumbnailEl.classList.remove(CLASS_BOX_PREVIEW_THUMBNAIL_IS_SELECTED);
+                thumbnailEl.removeAttribute('aria-current');
             }
         });
     }
diff --git a/src/lib/__tests__/ThumbnailsSidebar-test.js b/src/lib/__tests__/ThumbnailsSidebar-test.js
index 44f5c360c..9fdd77d95 100644
--- a/src/lib/__tests__/ThumbnailsSidebar-test.js
+++ b/src/lib/__tests__/ThumbnailsSidebar-test.js
@@ -439,6 +439,8 @@ describe('ThumbnailsSidebar', () => {
         beforeEach(() => {
             stubs.addClass = jest.fn();
             stubs.removeClass = jest.fn();
+            stubs.addAriaAttribute = jest.fn();
+            stubs.removeAriaAttribute = jest.fn();
 
             // eslint-disable-next-line
             const createTestThumbnail = pageNum => {
@@ -446,6 +448,8 @@ describe('ThumbnailsSidebar', () => {
                 thumbnail.dataset.bpPageNum = pageNum;
                 thumbnail.classList.add = stubs.addClass;
                 thumbnail.classList.remove = stubs.removeClass;
+                thumbnail.setAttribute = stubs.addAriaAttribute;
+                thumbnail.removeAttribute = stubs.removeAriaAttribute;
                 return thumbnail;
             };
 
@@ -475,6 +479,22 @@ describe('ThumbnailsSidebar', () => {
             expect(stubs.removeClass).toBeCalledTimes(2);
             expect(stubs.addClass).toBeCalledTimes(1);
         });
+
+        test('should add the aria-current attribute when thumbnail is selected', () => {
+            thumbnailsSidebar.currentPage = 2;
+
+            thumbnailsSidebar.applyCurrentPageSelection();
+
+            expect(stubs.addAriaAttribute).toBeCalledTimes(1);
+        });
+
+        test('should remove the aria-current attribute when thumbnail is not selected', () => {
+            thumbnailsSidebar.currentPage = 2;
+
+            thumbnailsSidebar.applyCurrentPageSelection();
+
+            expect(stubs.removeAriaAttribute).toBeCalledTimes(2);
+        });
     });
 
     describe('toggle()', () => {