diff --git a/internal/events/events.go b/internal/events/events.go
index 84933cc9..2d5f6683 100644
--- a/internal/events/events.go
+++ b/internal/events/events.go
@@ -35,3 +35,7 @@ func (eventBase) _isEvent() {}
 type EventPublisher interface {
 	PublishEvent(ctx context.Context, event Event)
 }
+
+type NullEventPublisher struct{}
+
+func (NullEventPublisher) PublishEvent(_ context.Context, _ Event) {}
diff --git a/internal/user/user.go b/internal/user/user.go
index f1691a61..2fdbb86a 100644
--- a/internal/user/user.go
+++ b/internal/user/user.go
@@ -42,6 +42,8 @@ import (
 	"github.com/ProtonMail/proton-bridge/v3/internal/safe"
 	"github.com/ProtonMail/proton-bridge/v3/internal/services/sendrecorder"
 	"github.com/ProtonMail/proton-bridge/v3/internal/services/smtp"
+	"github.com/ProtonMail/proton-bridge/v3/internal/services/userevents"
+	"github.com/ProtonMail/proton-bridge/v3/internal/services/useridentity"
 	"github.com/ProtonMail/proton-bridge/v3/internal/telemetry"
 	"github.com/ProtonMail/proton-bridge/v3/internal/usertypes"
 	"github.com/ProtonMail/proton-bridge/v3/internal/vault"
@@ -97,14 +99,15 @@ type User struct {
 
 	maxSyncMemory uint64
 
-	panicHandler async.PanicHandler
-
+	panicHandler     async.PanicHandler
 	configStatus     *configstatus.ConfigurationStatus
 	telemetryManager telemetry.Availability
 	// goStatusProgress triggers a check/sending if progress is needed.
 	goStatusProgress func()
 
-	smtpService *smtp.Service
+	eventService    *userevents.Service
+	identityService *useridentity.Service
+	smtpService     *smtp.Service
 }
 
 // New returns a new user.
@@ -134,6 +137,8 @@ func New(
 		return nil, fmt.Errorf("failed to get labels: %w", err)
 	}
 
+	identityState := useridentity.NewState(apiUser, slices.Clone(apiAddrs), client)
+
 	logrus.WithFields(logrus.Fields{
 		"userID":    apiUser.ID,
 		"numAddr":   len(apiAddrs),
@@ -146,6 +151,28 @@ func New(
 		return nil, fmt.Errorf("failed to init configuration status file: %w", err)
 	}
 
+	// Use null publisher for now to avoid conflicts with original event loop.
+	eventPublisher := &events.NullEventPublisher{}
+
+	// Use in memory store to avoid conflicts with original event loop.
+	idStore := userevents.NewInMemoryEventIDStore()
+	_ = idStore.Store(context.Background(), encVault.EventID())
+
+	eventService := userevents.NewService(
+		apiUser.ID,
+		client,
+		// Use in memory store to avoid conflicts with the original event loop.
+		idStore,
+		eventPublisher,
+		EventPeriod,
+		5*time.Minute,
+		crashHandler,
+	)
+
+	sendRecorder := sendrecorder.NewSendRecorder(sendrecorder.SendEntryExpiry)
+
+	identityService := useridentity.NewService(eventService, eventPublisher, identityState)
+
 	// Create the user object.
 	user := &User{
 		log: logrus.WithField("userID", apiUser.ID),
@@ -153,7 +180,7 @@ func New(
 		vault:    encVault,
 		client:   client,
 		reporter: reporter,
-		sendHash: sendrecorder.NewSendRecorder(sendrecorder.SendEntryExpiry),
+		sendHash: sendRecorder,
 
 		eventCh:   async.NewQueuedChannel[events.Event](0, 0, crashHandler, fmt.Sprintf("bridge-user-%v", apiUser.ID)),
 		eventLock: safe.NewRWMutex(),
@@ -181,9 +208,25 @@ func New(
 
 		configStatus:     configStatus,
 		telemetryManager: telemetryManager,
+
+		identityService: identityService,
+		smtpService:     nil,
+		eventService:    eventService,
 	}
 
-	user.smtpService = smtp.NewService(user, client, user.sendHash, user.panicHandler, user.reporter)
+	user.smtpService = smtp.NewService(
+		apiUser.ID,
+		client,
+		sendRecorder,
+		crashHandler,
+		reporter,
+		encVault,
+		encVault,
+		user,
+		eventService,
+		vaultToSMTPAddressMode(encVault.AddressMode()),
+		identityState.Clone(),
+	)
 
 	// Check for status_progress when triggered.
 	user.goStatusProgress = user.tasks.PeriodicOrTrigger(configstatus.ProgressCheckInterval, 0, func(ctx context.Context) {
@@ -271,9 +314,21 @@ func New(
 		}
 	})
 
+	// Start Event Service
+	if err := user.eventService.Start(ctx, user.tasks); err != nil {
+		return nil, fmt.Errorf("failed to start event service: %w", err)
+	}
+
+	// Start Identity Service
+	user.identityService.Start(user.tasks)
+
 	// Start SMTP Service
 	user.smtpService.Start(user.tasks)
 
+	if err := user.eventService.Resume(ctx); err != nil {
+		return nil, fmt.Errorf("failed to resume event service")
+	}
+
 	return user, nil
 }
 
@@ -336,7 +391,7 @@ func (user *User) GetAddressMode() vault.AddressMode {
 }
 
 // SetAddressMode sets the user's address mode.
-func (user *User) SetAddressMode(_ context.Context, mode vault.AddressMode) error {
+func (user *User) SetAddressMode(ctx context.Context, mode vault.AddressMode) error {
 	user.log.WithField("mode", mode).Info("Setting address mode")
 
 	user.syncAbort.Abort()
@@ -347,6 +402,10 @@ func (user *User) SetAddressMode(_ context.Context, mode vault.AddressMode) erro
 			return fmt.Errorf("failed to set address mode: %w", err)
 		}
 
+		if err := user.smtpService.SetAddressMode(ctx, vaultToSMTPAddressMode(mode)); err != nil {
+			return fmt.Errorf("failed to set smtp address mode: %w", err)
+		}
+
 		if err := user.clearSyncStatus(); err != nil {
 			return fmt.Errorf("failed to clear sync status: %w", err)
 		}
@@ -617,6 +676,9 @@ func (user *User) Close() {
 	// Close the user's notify channel.
 	user.eventCh.CloseAndDiscardQueued()
 
+	// Cleanup Event Service.
+	user.eventService.Close()
+
 	// Close the user's vault.
 	if err := user.vault.Close(); err != nil {
 		user.log.WithError(err).Error("Failed to close vault")
@@ -855,3 +917,15 @@ func sleepCtx(ctx context.Context, d time.Duration) {
 	case <-time.After(d):
 	}
 }
+
+func vaultToSMTPAddressMode(mode vault.AddressMode) smtp.AddressMode {
+	var smtpAddressMode smtp.AddressMode
+
+	if mode == vault.SplitMode {
+		smtpAddressMode = smtp.AddressModeSplit
+	} else {
+		smtpAddressMode = smtp.AddressModeCombined
+	}
+
+	return smtpAddressMode
+}