diff --git a/msgconv/from-signal.go b/msgconv/from-signal.go
index 8a4b5d14..918c749c 100644
--- a/msgconv/from-signal.go
+++ b/msgconv/from-signal.go
@@ -173,12 +173,16 @@ func (mc *MessageConverter) ConvertDisappearingTimerChangeToMatrix(ctx context.C
 	if timer == 0 {
 		part.Content.Body = "Disappearing messages disabled"
 	}
-	if updatePortal && !mc.NoUpdateDisappearing {
-		portal := mc.GetData(ctx)
-		portal.ExpirationTime = timer
-		err := portal.Update(ctx)
-		if err != nil {
-			zerolog.Ctx(ctx).Err(err).Msg("Failed to update portal disappearing timer in database")
+	if updatePortal {
+		if mc.UpdateDisappearing != nil {
+			mc.UpdateDisappearing(ctx, time.Duration(timer)*time.Second)
+		} else {
+			portal := mc.GetData(ctx)
+			portal.ExpirationTime = timer
+			err := portal.Update(ctx)
+			if err != nil {
+				zerolog.Ctx(ctx).Err(err).Msg("Failed to update portal disappearing timer in database")
+			}
 		}
 	}
 	return part
diff --git a/msgconv/msgconv.go b/msgconv/msgconv.go
index 33ac4a5b..ee3ff559 100644
--- a/msgconv/msgconv.go
+++ b/msgconv/msgconv.go
@@ -18,6 +18,7 @@ package msgconv
 
 import (
 	"context"
+	"time"
 
 	"maunium.net/go/mautrix/event"
 	"maunium.net/go/mautrix/id"
@@ -54,7 +55,7 @@ type MessageConverter struct {
 	ConvertGIFToAPNG     bool
 	MaxFileSize          int64
 	AsyncFiles           bool
-	NoUpdateDisappearing bool
+	UpdateDisappearing   func(ctx context.Context, newTimer time.Duration)
 
 	LocationFormat string
 }
diff --git a/pkg/connector/connector.go b/pkg/connector/connector.go
index 8aec917a..dcb7ada0 100644
--- a/pkg/connector/connector.go
+++ b/pkg/connector/connector.go
@@ -20,10 +20,13 @@ import (
 	"context"
 	"fmt"
 	"text/template"
+	"time"
 
 	"github.com/google/uuid"
+	"github.com/rs/zerolog"
 	"go.mau.fi/util/dbutil"
 	"maunium.net/go/mautrix/bridgev2"
+	"maunium.net/go/mautrix/bridgev2/database"
 	"maunium.net/go/mautrix/bridgev2/networkid"
 	"maunium.net/go/mautrix/id"
 
@@ -124,7 +127,19 @@ func (s *SignalConnector) Init(bridge *bridgev2.Bridge) {
 		MaxFileSize:          50 * 1024 * 1024,
 		AsyncFiles:           true,
 		LocationFormat:       s.Config.LocationFormat,
-		NoUpdateDisappearing: true,
+		UpdateDisappearing: func(ctx context.Context, newTimer time.Duration) {
+			portal := ctx.Value(msgconvContextKey).(*msgconvContext).Portal
+			portal.Metadata.DisappearTimer = newTimer
+			if newTimer == 0 {
+				portal.Metadata.DisappearType = ""
+			} else {
+				portal.Metadata.DisappearType = database.DisappearingTypeAfterRead
+			}
+			err := portal.Save(ctx)
+			if err != nil {
+				zerolog.Ctx(ctx).Err(err).Msg("Failed to update portal disappearing timer in database")
+			}
+		},
 	}
 }
 
diff --git a/pkg/connector/handlesignal.go b/pkg/connector/handlesignal.go
index 6af25ab2..5d10716e 100644
--- a/pkg/connector/handlesignal.go
+++ b/pkg/connector/handlesignal.go
@@ -23,10 +23,12 @@ import (
 
 	"github.com/google/uuid"
 	"github.com/rs/zerolog"
+	"go.mau.fi/util/exfmt"
 	"go.mau.fi/util/exzerolog"
 	"maunium.net/go/mautrix/bridgev2"
 	"maunium.net/go/mautrix/bridgev2/database"
 	"maunium.net/go/mautrix/bridgev2/networkid"
+	"maunium.net/go/mautrix/event"
 
 	"go.mau.fi/mautrix-signal/pkg/signalmeow/events"
 	signalpb "go.mau.fi/mautrix-signal/pkg/signalmeow/protobuf"
@@ -235,13 +237,20 @@ func (evt *Bv2ChatEvent) ConvertMessage(ctx context.Context, portal *bridgev2.Po
 		if portal.Metadata.DisappearTimer != disappear.Timer {
 			portal.Metadata.DisappearType = disappear.Type
 			portal.Metadata.DisappearTimer = disappear.Timer
-			// TODO if the message doesn't have the DataMessage_EXPIRATION_TIMER_UPDATE,
-			//      we should send a message to the portal notifying of the implicit update
 			err := portal.Save(ctx)
 			if err != nil {
-				zerolog.Ctx(ctx).Err(err).Msg("Failed to save portal metadata after updating disappearing timer")
+				zerolog.Ctx(ctx).Err(err).Msg("Failed to save portal metadata after implicitly updating disappearing timer")
 			} else {
-				zerolog.Ctx(ctx).Debug().Dur("new_timer", portal.Metadata.DisappearTimer).Msg("Updated disappearing timer in portal")
+				zerolog.Ctx(ctx).Debug().Dur("new_timer", portal.Metadata.DisappearTimer).Msg("Implicitly updated disappearing timer in portal")
+			}
+			_, err = portal.Bridge.Bot.SendMessage(ctx, portal.MXID, event.EventMessage, &event.Content{
+				Parsed: &event.MessageEventContent{
+					MsgType: event.MsgNotice,
+					Body:    fmt.Sprintf("Automatically enabled disappearing message timer (%s) because incoming message is disappearing", exfmt.Duration(disappear.Timer)),
+				},
+			}, time.UnixMilli(int64(dataMsg.GetTimestamp())))
+			if err != nil {
+				zerolog.Ctx(ctx).Err(err).Msg("Failed to send notice about disappearing message timer changing implicitly")
 			}
 		}
 	}