diff --git a/e2e/tests/journeys.spec.ts b/e2e/tests/journeys.spec.ts
index c168add..15744d8 100644
--- a/e2e/tests/journeys.spec.ts
+++ b/e2e/tests/journeys.spec.ts
@@ -305,6 +305,30 @@ test('school type and gender switch straight to another value', async ({ page })
   await expect.poll(() => type.locator('option').allTextContents()).toEqual(offered);
 });
 
+/*
+ * School type offers six groups a parent recognises, and Faith sits beside it.
+ * Data-invariant: asserts what every returned school is, never how many.
+ */
+test('school type groups and the faith filter narrow to what they name', async ({ page }) => {
+  await page.goto('/?search=school');
+  const type = page.getByRole('combobox', { name: 'School type', exact: true });
+  await expect(type).toBeVisible({ timeout: 15_000 });
+  await type.selectOption({ label: 'Special school (SEND)' });
+  await expect(page).toHaveURL(/[?&]school_type=special(&|$)/);
+
+  await page.getByRole('button', { name: /^More filters/ }).click();
+  await page.getByRole('combobox', { name: 'Faith', exact: true }).selectOption({ label: 'Roman Catholic' });
+  await expect(page).toHaveURL(/[?&]faith=roman_catholic(&|$)/);
+
+  const res = await page.request.get(
+    '/api/schools?search=school&school_type=special&faith=roman_catholic&page_size=100');
+  expect(res.ok()).toBeTruthy();
+  for (const s of (await res.json()).schools as { school_type: string; religious_denomination: string }[]) {
+    expect(s.school_type).toMatch(/special/i);
+    expect(s.religious_denomination).toMatch(/catholic/i);
+  }
+});
+
 test('a phase outside primary/secondary filters to that phase, not to everything', async ({ page }) => {
   // The search page offers every GIAS phase, but the API only knew the grouped
   // ones and silently dropped the rest — so "Nursery" returned primaries.