diff --git a/apps/calendar/apps/web/src/lib/api/reminders.test.ts b/apps/calendar/apps/web/src/lib/api/reminders.test.ts
new file mode 100644
index 000000000..b9a1224e0
--- /dev/null
+++ b/apps/calendar/apps/web/src/lib/api/reminders.test.ts
@@ -0,0 +1,83 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+vi.mock('./client', () => ({
+	fetchApi: vi.fn(),
+}));
+
+import { fetchApi } from './client';
+import { getReminders, createReminder, deleteReminder } from './reminders';
+
+const mockFetchApi = vi.mocked(fetchApi);
+
+describe('reminders API client', () => {
+	beforeEach(() => {
+		vi.clearAllMocks();
+	});
+
+	describe('getReminders', () => {
+		it('should GET /events/:eventId/reminders', async () => {
+			mockFetchApi.mockResolvedValue({
+				data: [
+					{ id: 'rem-1', eventId: 'evt-1', minutesBefore: 15, status: 'pending' },
+					{ id: 'rem-2', eventId: 'evt-1', minutesBefore: 60, status: 'sent' },
+				],
+				error: null,
+			});
+
+			const result = await getReminders('evt-1');
+
+			expect(mockFetchApi).toHaveBeenCalledWith('/events/evt-1/reminders');
+			expect(result.data).toHaveLength(2);
+		});
+
+		it('should return error on failure', async () => {
+			mockFetchApi.mockResolvedValue({
+				data: null,
+				error: { message: 'Not found', code: 'NOT_FOUND', status: 404 },
+			});
+
+			const result = await getReminders('nonexistent');
+
+			expect(result.error).toBeTruthy();
+		});
+	});
+
+	describe('createReminder', () => {
+		it('should POST to /events/:eventId/reminders with body', async () => {
+			mockFetchApi.mockResolvedValue({
+				data: { id: 'rem-new', eventId: 'evt-1', minutesBefore: 30, status: 'pending' },
+				error: null,
+			});
+
+			const result = await createReminder('evt-1', {
+				eventId: 'evt-1',
+				minutesBefore: 30,
+				notifyPush: true,
+				notifyEmail: false,
+			});
+
+			expect(mockFetchApi).toHaveBeenCalledWith('/events/evt-1/reminders', {
+				method: 'POST',
+				body: {
+					eventId: 'evt-1',
+					minutesBefore: 30,
+					notifyPush: true,
+					notifyEmail: false,
+				},
+			});
+			expect(result.data).toBeTruthy();
+		});
+	});
+
+	describe('deleteReminder', () => {
+		it('should DELETE /reminders/:id', async () => {
+			mockFetchApi.mockResolvedValue({ data: null, error: null });
+
+			await deleteReminder('rem-1');
+
+			expect(mockFetchApi).toHaveBeenCalledWith('/reminders/rem-1', {
+				method: 'DELETE',
+			});
+		});
+	});
+});