diff --git a/app/assets/javascripts/radioSelect.js b/app/assets/javascripts/radioSelect.js
index fbd4175b9..53c8d7f37 100644
--- a/app/assets/javascripts/radioSelect.js
+++ b/app/assets/javascripts/radioSelect.js
@@ -17,7 +17,7 @@
       {{/showNowAsDefault}}
       <div class="radio-select__column">
         {{#categories}}
-          <input type='button' class='govuk-button govuk-button--secondary radio-select__button--category' value='{{.}}' />
+          <input type='button' class='govuk-button govuk-button--secondary radio-select__button--category' aria-expanded="false" value='{{.}}' />
         {{/categories}}
       </div>
     `),
@@ -37,7 +37,7 @@
             <label for="{{id}}">{{label}}</label>
           </div>
         {{/choices}}
-        <input type='button' class='govuk-button govuk-button--secondary radio-select__button--done' value='Done' />
+        <input type='button' class='govuk-button govuk-button--secondary radio-select__button--done' aria-expanded='true' value='Done' />
       </div>
     `),
     'chosen': Hogan.compile(`
@@ -58,7 +58,7 @@
         {{/choices}}
       </div>
       <div class="radio-select__column">
-        <input type='button' class='govuk-button govuk-button--secondary radio-select__button--reset' value='Choose a different time' />
+        <input type='button' class='govuk-button govuk-button--secondary radio-select__button--reset' aria-expanded='false' value='Choose a different time' />
       </div>
     `)
   };
diff --git a/tests/javascripts/radioSelect.test.js b/tests/javascripts/radioSelect.test.js
index 4ab998df1..ab5420e07 100644
--- a/tests/javascripts/radioSelect.test.js
+++ b/tests/javascripts/radioSelect.test.js
@@ -179,6 +179,14 @@ describe('RadioSelect', () => {
 
       });
 
+      test("each button's semantics should show it controls another region and that region is collapsed", () => {
+
+        categoryButtons.forEach(btn => {
+          expect(btn.getAttribute('aria-expanded')).toEqual('false');
+        });
+
+      });
+
     });
 
   });
@@ -241,6 +249,7 @@ describe('RadioSelect', () => {
 
       expect(button).not.toBeNull();
       expect(button.getAttribute('value')).toEqual('Done');
+      expect(button.getAttribute('aria-expanded')).toEqual('true');
 
     });