diff --git a/internal/service/auth.go b/internal/service/auth.go
index 4b24563..584ce04 100644
--- a/internal/service/auth.go
+++ b/internal/service/auth.go
@@ -72,6 +72,7 @@ func (s *AuthService) Register(ctx context.Context, username, email, password st
 		Username:     username,
 		Email:        email,
 		PasswordHash: passwordHash,
+		Status:       model.StatusActive,
 	}
 
 	if err := s.userRepo.Create(ctx, user); err != nil {
@@ -94,6 +95,10 @@ func (s *AuthService) Login(ctx context.Context, email, password string) (*Token
 		return nil, model.NewInternalError("find user", err)
 	}
 
+	if user.Status != model.StatusActive {
+		return nil, &model.AppError{Status: http.StatusUnauthorized, Message: "invalid email or password"}
+	}
+
 	if err := auth.VerifyPassword(user.PasswordHash, password); err != nil {
 		return nil, &model.AppError{Status: http.StatusUnauthorized, Message: "invalid email or password"}
 	}
@@ -126,6 +131,14 @@ func (s *AuthService) Refresh(ctx context.Context, refreshTokenStr string) (*Tok
 		return nil, &model.AppError{Status: http.StatusUnauthorized, Message: "invalid token"}
 	}
 
+	user, err := s.userRepo.FindByID(ctx, claims.UserID)
+	if err != nil {
+		return nil, &model.AppError{Status: http.StatusUnauthorized, Message: "invalid token"}
+	}
+	if user.Status != model.StatusActive {
+		return nil, &model.AppError{Status: http.StatusUnauthorized, Message: "invalid token"}
+	}
+
 	if err := s.sessionRepo.Delete(ctx, session.ID); err != nil {
 		return nil, model.NewInternalError("delete old session", err)
 	}
@@ -188,6 +201,14 @@ func (s *AuthService) LoginWithPasskey(ctx context.Context, tokenStr string) (*T
 		return nil, model.NewInternalError("find credential", err)
 	}
 
+	user, err := s.userRepo.FindByIDIncludeDeleted(ctx, cred.UserID)
+	if err != nil {
+		return nil, model.NewInternalError("find user", err)
+	}
+	if user.Status != model.StatusActive {
+		return nil, &model.AppError{Status: http.StatusUnauthorized, Message: "invalid passkey"}
+	}
+
 	if cred.Type != "app_passkey" {
 		return nil, &model.AppError{Status: http.StatusUnauthorized, Message: "invalid credential type"}
 	}
diff --git a/internal/service/auth_test.go b/internal/service/auth_test.go
index 3901c7f..767edce 100644
--- a/internal/service/auth_test.go
+++ b/internal/service/auth_test.go
@@ -16,6 +16,13 @@ import (
 )
 
 func setupAuthService(t *testing.T) *AuthService {
+	svc, _ := setupAuthServiceWithRepos(t)
+	return svc
+}
+
+// setupAuthServiceWithRepos creates an AuthService and returns the UserRepository
+// for tests that need direct repo access (e.g., soft-deleting users).
+func setupAuthServiceWithRepos(t *testing.T) (*AuthService, repository.UserRepository) {
 	t.Helper()
 
 	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{})
@@ -30,12 +37,13 @@ func setupAuthService(t *testing.T) *AuthService {
 	sessionRepo := repository.NewSessionRepository(db)
 	credentialRepo := repository.NewCredentialRepository(db)
 
-	return NewAuthService(
+	svc := NewAuthService(
 		userRepo, sessionRepo, credentialRepo,
 		[]byte("test-secret"),
 		15*time.Minute,
 		7*24*time.Hour,
 	)
+	return svc, userRepo
 }
 
 func TestAuthService_Register(t *testing.T) {
@@ -404,3 +412,152 @@ func TestAuthService_RefreshWithAccessToken(t *testing.T) {
 		t.Fatal("expected error when using access token for refresh, got nil")
 	}
 }
+
+func TestAuthService_LoginDisabledUser(t *testing.T) {
+	svc, userRepo := setupAuthServiceWithRepos(t)
+	ctx := context.Background()
+
+	user, err := svc.Register(ctx, "alice", "alice@example.com", "password123")
+	if err != nil {
+		t.Fatalf("Register = %v", err)
+	}
+
+	if err := userRepo.Delete(ctx, user.ID); err != nil {
+		t.Fatalf("Delete = %v", err)
+	}
+
+	_, err = svc.Login(ctx, "alice@example.com", "password123")
+	if err == nil {
+		t.Fatal("expected error for disabled user login, got nil")
+	}
+	var ae *model.AppError
+	if !errors.As(err, &ae) {
+		t.Fatalf("expected AppError, got %T: %v", err, err)
+	}
+	if ae.Status != http.StatusUnauthorized {
+		t.Errorf("status = %d, want %d", ae.Status, http.StatusUnauthorized)
+	}
+	if ae.Message != "invalid email or password" {
+		t.Errorf("message = %q, want %q", ae.Message, "invalid email or password")
+	}
+}
+
+func TestAuthService_LoginDisabledUserSameMessage(t *testing.T) {
+	svc, userRepo := setupAuthServiceWithRepos(t)
+	ctx := context.Background()
+
+	user, err := svc.Register(ctx, "alice", "alice@example.com", "password123")
+	if err != nil {
+		t.Fatalf("Register = %v", err)
+	}
+
+	// Get error for wrong password (active user)
+	_, wrongPwErr := svc.Login(ctx, "alice@example.com", "wrongpassword")
+
+	// Soft-delete user, then try to login
+	if err := userRepo.Delete(ctx, user.ID); err != nil {
+		t.Fatalf("Delete = %v", err)
+	}
+	_, disabledErr := svc.Login(ctx, "alice@example.com", "password123")
+
+	// Both errors should have the same message (no user enumeration)
+	if disabledErr == nil {
+		t.Fatal("expected error for disabled user login, got nil")
+	}
+	var aeDisabled *model.AppError
+	if !errors.As(disabledErr, &aeDisabled) {
+		t.Fatalf("expected AppError, got %T: %v", disabledErr, disabledErr)
+	}
+
+	var aeWrongPw *model.AppError
+	if !errors.As(wrongPwErr, &aeWrongPw) {
+		t.Fatalf("expected AppError for wrong password, got %T: %v", wrongPwErr, wrongPwErr)
+	}
+
+	if aeDisabled.Message != aeWrongPw.Message {
+		t.Errorf("disabled message = %q, want %q (must match wrong-password message to prevent user enumeration)", aeDisabled.Message, aeWrongPw.Message)
+	}
+	if aeDisabled.Message != "invalid email or password" {
+		t.Errorf("disabled message = %q, want %q", aeDisabled.Message, "invalid email or password")
+	}
+}
+
+func TestAuthService_LoginWithPasskeyDisabledUser(t *testing.T) {
+	svc, userRepo := setupAuthServiceWithRepos(t)
+	ctx := context.Background()
+
+	user, err := svc.Register(ctx, "alice", "alice@example.com", "password123")
+	if err != nil {
+		t.Fatalf("Register = %v", err)
+	}
+
+	pair, err := svc.Login(ctx, "alice@example.com", "password123")
+	if err != nil {
+		t.Fatalf("Login = %v", err)
+	}
+
+	claims, err := auth.ParseToken(pair.AccessToken, []byte("test-secret"))
+	if err != nil {
+		t.Fatalf("ParseToken = %v", err)
+	}
+
+	pk, err := svc.CreatePasskey(ctx, claims.UserID, "My Phone")
+	if err != nil {
+		t.Fatalf("CreatePasskey = %v", err)
+	}
+
+	// Soft-delete the user
+	if err := userRepo.Delete(ctx, user.ID); err != nil {
+		t.Fatalf("Delete = %v", err)
+	}
+
+	_, err = svc.LoginWithPasskey(ctx, pk.Raw)
+	if err == nil {
+		t.Fatal("expected error for disabled user passkey login, got nil")
+	}
+	var ae *model.AppError
+	if !errors.As(err, &ae) {
+		t.Fatalf("expected AppError, got %T: %v", err, err)
+	}
+	if ae.Status != http.StatusUnauthorized {
+		t.Errorf("status = %d, want %d", ae.Status, http.StatusUnauthorized)
+	}
+	if ae.Message != "invalid passkey" {
+		t.Errorf("message = %q, want %q", ae.Message, "invalid passkey")
+	}
+}
+
+func TestAuthService_RefreshDisabledUser(t *testing.T) {
+	svc, userRepo := setupAuthServiceWithRepos(t)
+	ctx := context.Background()
+
+	user, err := svc.Register(ctx, "alice", "alice@example.com", "password123")
+	if err != nil {
+		t.Fatalf("Register = %v", err)
+	}
+
+	pair, err := svc.Login(ctx, "alice@example.com", "password123")
+	if err != nil {
+		t.Fatalf("Login = %v", err)
+	}
+
+	// Soft-delete the user
+	if err := userRepo.Delete(ctx, user.ID); err != nil {
+		t.Fatalf("Delete = %v", err)
+	}
+
+	_, err = svc.Refresh(ctx, pair.RefreshToken)
+	if err == nil {
+		t.Fatal("expected error for disabled user refresh, got nil")
+	}
+	var ae *model.AppError
+	if !errors.As(err, &ae) {
+		t.Fatalf("expected AppError, got %T: %v", err, err)
+	}
+	if ae.Status != http.StatusUnauthorized {
+		t.Errorf("status = %d, want %d", ae.Status, http.StatusUnauthorized)
+	}
+	if ae.Message != "invalid token" {
+		t.Errorf("message = %q, want %q", ae.Message, "invalid token")
+	}
+}