diff --git a/src/lib/server/email/__tests__/email-system.test.ts b/src/lib/server/email/__tests__/email-system.test.ts
index 1f7b0e3..d5d2fac 100644
--- a/src/lib/server/email/__tests__/email-system.test.ts
+++ b/src/lib/server/email/__tests__/email-system.test.ts
@@ -467,7 +467,13 @@ describe("Email System", () => {
       const confirmationCode = "ABC123";
       const expirationMinutes = 15;
 
-      await sendConfirmationEmail(staffUser, mockTenant, confirmationCode, expirationMinutes);
+      await sendConfirmationEmail(
+        staffUser,
+        mockTenant,
+        confirmationCode,
+        expirationMinutes,
+        new URL("https://example.com"),
+      );
 
       expect(mockSendMail).toHaveBeenCalled();
     });
@@ -506,7 +512,13 @@ describe("Email System", () => {
       const confirmationCode = "XYZ789";
       const expirationMinutes = 10;
 
-      await sendConfirmationEmail(staffUser, mockTenant, confirmationCode, expirationMinutes);
+      await sendConfirmationEmail(
+        staffUser,
+        mockTenant,
+        confirmationCode,
+        expirationMinutes,
+        new URL("https://example.com"),
+      );
 
       expect(mockSendMail).toHaveBeenCalled();
     });
diff --git a/src/lib/server/email/email-service.ts b/src/lib/server/email/email-service.ts
index cb40937..596bd54 100644
--- a/src/lib/server/email/email-service.ts
+++ b/src/lib/server/email/email-service.ts
@@ -433,7 +433,7 @@ export async function sendConfirmationEmail(
   tenant: SelectTenant,
   confirmationCode: string,
   expirationMinutes: number = 15,
-  requestUrl?: URL,
+  requestUrl: URL,
 ): Promise<void> {
   // Generate appropriate base URL if request URL is provided
   const baseUrl = requestUrl ? generateBaseUrl(requestUrl, tenant) : "http://localhost:5173";
diff --git a/src/lib/server/services/__tests__/user-service.test.ts b/src/lib/server/services/__tests__/user-service.test.ts
index 97027bb..7518dbe 100644
--- a/src/lib/server/services/__tests__/user-service.test.ts
+++ b/src/lib/server/services/__tests__/user-service.test.ts
@@ -124,7 +124,7 @@ describe("UserService", () => {
         .mockReturnValueOnce(mockInviteInsertBuilder)
         .mockReturnValueOnce(mockInsertBuilder);
 
-      const result = await UserService.createUser(adminData);
+      const result = await UserService.createUser(adminData, new URL("http://localhost:5173"));
 
       expect(mockCentralDb.insert).toHaveBeenCalled();
       expect(mockInsertBuilder.values).toHaveBeenCalledWith({
@@ -158,7 +158,7 @@ describe("UserService", () => {
 
       mockCentralDb.update.mockReturnValue(mockUpdateBuilder);
 
-      await UserService.resendConfirmationEmail(email);
+      await UserService.resendConfirmationEmail(email, new URL("http://localhost:5173"));
 
       expect(mockCentralDb.update).toHaveBeenCalled();
       expect(mockUpdateBuilder.set).toHaveBeenCalledWith({
@@ -180,7 +180,9 @@ describe("UserService", () => {
 
       mockCentralDb.update.mockReturnValue(mockUpdateBuilder);
 
-      await expect(UserService.resendConfirmationEmail(email)).rejects.toThrow(NotFoundError);
+      await expect(
+        UserService.resendConfirmationEmail(email, new URL("http://localhost:5173")),
+      ).rejects.toThrow(NotFoundError);
     });
   });
 
diff --git a/src/lib/server/services/user-service.ts b/src/lib/server/services/user-service.ts
index 6ae3399..605e2b4 100644
--- a/src/lib/server/services/user-service.ts
+++ b/src/lib/server/services/user-service.ts
@@ -98,7 +98,7 @@ export class UserService {
   /**
    * Create a new user
    */
-  static async createUser(userData: UserCreation, requestUrl?: URL) {
+  static async createUser(userData: UserCreation, requestUrl: URL) {
     const log = logger.setContext("UserService");
     log.debug("Creating new user account", {
       email: userData.email,
@@ -218,9 +218,9 @@ export class UserService {
   /**
    * Resend the confirmation email for a user
    * @param email - Email of the user to confirm
-   * @param requestUrl - Optional request URL for generating correct baseUrl
+   * @param requestUrl - request URL for generating correct baseUrl
    */
-  static async resendConfirmationEmail(email: string, requestUrl?: URL): Promise<void> {
+  static async resendConfirmationEmail(email: string, requestUrl: URL): Promise<void> {
     const log = logger.setContext("UserService");
     log.debug("Resending confirmation email", { email });
 
diff --git a/src/routes/api/auth/invite/+server.ts b/src/routes/api/auth/invite/+server.ts
index 3f865ae..54cc190 100644
--- a/src/routes/api/auth/invite/+server.ts
+++ b/src/routes/api/auth/invite/+server.ts
@@ -1,3 +1,4 @@
+import { dev } from "$app/environment";
 import { UniversalLogger } from "$lib/logger";
 import { sendConfirmationEmail } from "$lib/server/email/email-service";
 import { registerOpenAPIRoute } from "$lib/server/openapi";
@@ -205,7 +206,7 @@ export const POST: RequestHandler = async ({ request, locals, url }) => {
       tenant,
       invitation.inviteCode,
       10, // 10 minutes expiration to match tokenValidUntil
-      url,
+      dev ? url : new URL(`https://${tenant.domain}`),
     );
 
     logger.debug("User invitation sent successfully", {