diff --git a/comms/internal/rpcz/chat.go b/comms/internal/rpcz/chat.go
index 8bf44dec410..1e24409bea3 100644
--- a/comms/internal/rpcz/chat.go
+++ b/comms/internal/rpcz/chat.go
@@ -66,8 +66,13 @@ func chatSendMessage(tx *sqlx.Tx, userId int32, chatId string, messageId string,
 	return err
 }
 
-func chatReactMessage(tx *sqlx.Tx, userId int32, messageId string, reaction string, messageTimestamp time.Time) error {
-	_, err := tx.Exec("insert into chat_message_reactions (user_id, message_id, reaction, created_at, updated_at) values ($1, $2, $3, $4, $4) on conflict (user_id, message_id) do update set reaction = $3, updated_at = $4", userId, messageId, reaction, messageTimestamp)
+func chatReactMessage(tx *sqlx.Tx, userId int32, messageId string, reaction *string, messageTimestamp time.Time) error {
+	var err error
+	if reaction != nil {
+		_, err = tx.Exec("insert into chat_message_reactions (user_id, message_id, reaction, created_at, updated_at) values ($1, $2, $3, $4, $4) on conflict (user_id, message_id) do update set reaction = $3, updated_at = $4", userId, messageId, *reaction, messageTimestamp)
+	} else {
+		_, err = tx.Exec("delete from chat_message_reactions where user_id = $1 and message_id = $2", userId, messageId)
+	}
 	if err != nil {
 		return err
 	}
diff --git a/comms/internal/rpcz/chat_test.go b/comms/internal/rpcz/chat_test.go
index 9005fcebff8..54ecc2e2c98 100644
--- a/comms/internal/rpcz/chat_test.go
+++ b/comms/internal/rpcz/chat_test.go
@@ -72,11 +72,15 @@ func TestChat(t *testing.T) {
 		assert.Equal(t, expected, unreadCount)
 	}
 
-	assertReaction := func(userId int, messageId string, expected string) {
+	assertReaction := func(userId int, messageId string, expected *string) {
 		var reaction string
 		err := tx.Get(&reaction, "select reaction from chat_message_reactions where user_id = $1 and message_id = $2", userId, messageId)
-		assert.NoError(t, err)
-		assert.Equal(t, expected, reaction)
+		if expected != nil {
+			assert.NoError(t, err)
+			assert.Equal(t, *expected, reaction)
+		} else {
+			assert.ErrorIs(t, err, sql.ErrNoRows)
+		}
 	}
 
 	// assert sender has no unread messages
@@ -119,14 +123,19 @@ func TestChat(t *testing.T) {
 	// 91 reacts to 92's message
 	reactTs := time.Now()
 	reaction := "fire"
-	err = chatReactMessage(tx, 91, replyMessageId, reaction, reactTs)
-	assertReaction(91, replyMessageId, reaction)
+	err = chatReactMessage(tx, 91, replyMessageId, &reaction, reactTs)
+	assertReaction(91, replyMessageId, &reaction)
 
-	// 91 changes reaction to 92's old message
+	// 91 changes reaction to 92's message
 	changedReactTs := time.Now()
 	newReaction := "heart"
-	err = chatReactMessage(tx, 91, replyMessageId, newReaction, changedReactTs)
-	assertReaction(91, replyMessageId, newReaction)
+	err = chatReactMessage(tx, 91, replyMessageId, &newReaction, changedReactTs)
+	assertReaction(91, replyMessageId, &newReaction)
+
+	// 91 removes reaction to 92's message
+	removedReactTs := time.Now()
+	err = chatReactMessage(tx, 91, replyMessageId, nil, removedReactTs)
+	assertReaction(91, replyMessageId, nil)
 
 	tx.Rollback()
 }
diff --git a/comms/schema/schema.go b/comms/schema/schema.go
index 3f277051c76..f73ec50f6da 100644
--- a/comms/schema/schema.go
+++ b/comms/schema/schema.go
@@ -57,9 +57,9 @@ type ChatReactRPC struct {
 }
 
 type ChatReactRPCParams struct {
-	ChatID    string `json:"chat_id"`
-	MessageID string `json:"message_id"`
-	Reaction  string `json:"reaction"`
+	ChatID    string  `json:"chat_id"`
+	MessageID string  `json:"message_id"`
+	Reaction  *string `json:"reaction"`
 }
 
 type ChatReadRPC struct {
@@ -109,7 +109,7 @@ type RPCPayloadParams struct {
 	Message         *string           `json:"message,omitempty"`
 	MessageID       *string           `json:"message_id,omitempty"`
 	ParentMessageID *string           `json:"parent_message_id,omitempty"`
-	Reaction        *string           `json:"reaction,omitempty"`
+	Reaction        *string           `json:"reaction"`
 	UserID          *string           `json:"user_id,omitempty"`
 	Permit          *ChatPermission   `json:"permit,omitempty"`
 }
diff --git a/comms/schema/schema.ts b/comms/schema/schema.ts
index ee70498f034..eed787c8b79 100644
--- a/comms/schema/schema.ts
+++ b/comms/schema/schema.ts
@@ -44,7 +44,7 @@ export type ChatReactRPC = {
   params: {
     chat_id: string
     message_id: string
-    reaction: string
+    reaction: string | null
   }
 }
 
diff --git a/libs/src/sdk/api/chats/serverTypes.ts b/libs/src/sdk/api/chats/serverTypes.ts
index ee70498f034..eed787c8b79 100644
--- a/libs/src/sdk/api/chats/serverTypes.ts
+++ b/libs/src/sdk/api/chats/serverTypes.ts
@@ -44,7 +44,7 @@ export type ChatReactRPC = {
   params: {
     chat_id: string
     message_id: string
-    reaction: string
+    reaction: string | null
   }
 }