diff --git a/internal/user/smtp.go b/internal/user/smtp.go
index 9edc8243..7679e8eb 100644
--- a/internal/user/smtp.go
+++ b/internal/user/smtp.go
@@ -80,7 +80,7 @@ func sendWithKey( //nolint:funlen
 		return liteapi.Message{}, fmt.Errorf("failed to get armored message body: %w", err)
 	}
 
-	draft, err := createDraft(ctx, client, emails, from, to, parentID, liteapi.DraftTemplate{
+	draft, err := createDraft(ctx, client, emails, from, to, parentID, message.InReplyTo, liteapi.DraftTemplate{
 		Subject:  message.Subject,
 		Body:     armBody,
 		MIMEType: message.MIMEType,
@@ -196,6 +196,7 @@ func createDraft(
 	from string,
 	to []string,
 	parentID string,
+	replyToID string,
 	template liteapi.DraftTemplate,
 ) (liteapi.Message, error) {
 	// Check sender: set the sender if it's missing.
@@ -228,9 +229,18 @@ func createDraft(
 		}
 	}
 
+	var action liteapi.CreateDraftAction
+
+	if len(replyToID) > 0 {
+		action = liteapi.ReplyAction
+	} else {
+		action = liteapi.ForwardAction
+	}
+
 	return client.CreateDraft(ctx, liteapi.CreateDraftReq{
 		Message:  template,
 		ParentID: parentID,
+		Action:   action,
 	})
 }
 
diff --git a/pkg/message/parser.go b/pkg/message/parser.go
index 492e40e1..85d51703 100644
--- a/pkg/message/parser.go
+++ b/pkg/message/parser.go
@@ -48,6 +48,7 @@ type Message struct {
 	PlainBody   Body
 	Attachments []Attachment
 	MIMEType    rfc822.MIMEType
+	IsReply     bool
 
 	Subject  string
 	Sender   *mail.Address
@@ -58,6 +59,7 @@ type Message struct {
 
 	References []string
 	ExternalID string
+	InReplyTo  string
 }
 
 type Attachment struct {
@@ -491,6 +493,9 @@ func parseMessageHeader(h message.Header) (Message, error) { //nolint:funlen
 		case "message-id":
 			m.ExternalID = regexp.MustCompile("<(.*)>").ReplaceAllString(fields.Value(), "$1")
 
+		case "in-reply-to":
+			m.InReplyTo = regexp.MustCompile("<(.*)>").ReplaceAllString(fields.Value(), "$1")
+
 		case "references":
 			m.References = append(m.References, xslices.Map(strings.Fields(fields.Value()), func(ref string) string {
 				return strings.Trim(ref, "<>")