diff --git a/backend/internal/dto/user_dto.go b/backend/internal/dto/user_dto.go
index 75919bf6..47a3cca7 100644
--- a/backend/internal/dto/user_dto.go
+++ b/backend/internal/dto/user_dto.go
@@ -20,7 +20,7 @@ type UserCreateDto struct {
 	Username  string  `json:"username" binding:"required,username,min=2,max=50"`
 	Email     string  `json:"email" binding:"required,email"`
 	FirstName string  `json:"firstName" binding:"required,min=1,max=50"`
-	LastName  string  `json:"lastName" binding:"required,min=1,max=50"`
+	LastName  string  `json:"lastName" binding:"max=50"`
 	IsAdmin   bool    `json:"isAdmin"`
 	Locale    *string `json:"locale"`
 	Disabled  bool    `json:"disabled"`
diff --git a/frontend/src/lib/types/user.type.ts b/frontend/src/lib/types/user.type.ts
index b5f65dc3..a3c932ab 100644
--- a/frontend/src/lib/types/user.type.ts
+++ b/frontend/src/lib/types/user.type.ts
@@ -7,7 +7,7 @@ export type User = {
 	username: string;
 	email: string;
 	firstName: string;
-	lastName: string;
+	lastName?: string;
 	isAdmin: boolean;
 	userGroups: UserGroup[];
 	customClaims: CustomClaim[];
diff --git a/frontend/src/routes/settings/admin/users/user-form.svelte b/frontend/src/routes/settings/admin/users/user-form.svelte
index 5b35659c..72ab4325 100644
--- a/frontend/src/routes/settings/admin/users/user-form.svelte
+++ b/frontend/src/routes/settings/admin/users/user-form.svelte
@@ -30,7 +30,7 @@
 
 	const formSchema = z.object({
 		firstName: z.string().min(1).max(50),
-		lastName: z.string().min(1).max(50),
+		lastName: z.string().max(50),
 		username: z
 			.string()
 			.min(2)