diff --git a/plugins/cost-insights/src/components/PeriodSelect/PeriodSelect.test.tsx b/plugins/cost-insights/src/components/PeriodSelect/PeriodSelect.test.tsx
index d8535cf791..ae513c04e0 100644
--- a/plugins/cost-insights/src/components/PeriodSelect/PeriodSelect.test.tsx
+++ b/plugins/cost-insights/src/components/PeriodSelect/PeriodSelect.test.tsx
@@ -73,8 +73,9 @@ describe('<PeriodSelect />', () => {
     it(`Should select ${duration}`, async () => {
       const mockOnSelect = jest.fn();
       const mockAggregation =
+        // Can't select an option that's already the default
         DefaultPageFilters.duration === duration
-          ? Duration.P1M
+          ? Duration.P30D
           : DefaultPageFilters.duration;
 
       const rendered = await renderInTestApp(
@@ -88,7 +89,6 @@ describe('<PeriodSelect />', () => {
       const button = getByRole(periodSelect, 'button');
 
       UserEvent.click(button);
-      await waitFor(() => rendered.getByText('Past 60 Days'));
       UserEvent.click(rendered.getByTestId(`period-select-option-${duration}`));
       expect(mockOnSelect).toHaveBeenLastCalledWith(duration);
     });
diff --git a/plugins/cost-insights/src/utils/duration.ts b/plugins/cost-insights/src/utils/duration.ts
index 5a3fb52271..2ca2817324 100644
--- a/plugins/cost-insights/src/utils/duration.ts
+++ b/plugins/cost-insights/src/utils/duration.ts
@@ -60,10 +60,7 @@ export function exclusiveEndDateOf(
         .add(1, 'day')
         .format(DEFAULT_DATE_FORMAT);
     case Duration.P3M:
-      return moment(inclusiveEndDate)
-        .utc()
-        .startOf('quarter')
-        .format(DEFAULT_DATE_FORMAT);
+      return quarterEndDate(inclusiveEndDate);
     default:
       return assertNever(duration);
   }
@@ -83,3 +80,12 @@ export function inclusiveEndDateOf(
 export function intervalsOf(duration: Duration, inclusiveEndDate: string) {
   return `R2/${duration}/${exclusiveEndDateOf(duration, inclusiveEndDate)}`;
 }
+
+function quarterEndDate(inclusiveEndDate: string): string {
+  const endDate = moment(inclusiveEndDate).utc();
+  const endOfQuarter = endDate.endOf('quarter').format(DEFAULT_DATE_FORMAT);
+  if (endOfQuarter === inclusiveEndDate) {
+    return inclusiveEndDate;
+  }
+  return endDate.startOf('quarter').format(DEFAULT_DATE_FORMAT);
+}