diff --git a/src/client.ts b/src/client.ts
index 1319ced23..38af3c5c6 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -1971,8 +1971,8 @@ export class StreamChat<StreamChatGenerics extends ExtendableGenerics = DefaultG
     if (cid in this.activeChannels && !this.activeChannels[cid].disconnected) {
       const channel = this.activeChannels[cid];
       if (Object.keys(custom).length > 0) {
-        channel.data = custom;
-        channel._data = custom;
+        channel.data = { ...channel.data, ...custom };
+        channel._data = { ...channel._data, ...custom };
       }
       return channel;
     }
diff --git a/test/unit/channel.js b/test/unit/channel.js
index 1a04818ed..b72ec4b61 100644
--- a/test/unit/channel.js
+++ b/test/unit/channel.js
@@ -779,6 +779,17 @@ describe('Channels - Constructor', function () {
 		done();
 	});
 
+	it('custom data merges to the right with current data', function (done) {
+		let channel = client.channel('messaging', 'brand_new_123', { cool: true });
+		expect(channel.cid).to.eql('messaging:brand_new_123');
+		expect(channel.id).to.eql('brand_new_123');
+		expect(channel.data).to.eql({ cool: true });
+		channel = client.channel('messaging', 'brand_new_123', { custom_cool: true });
+		console.log(channel.data);
+		expect(channel.data).to.eql({ cool: true, custom_cool: true });
+		done();
+	});
+
 	it('default options', function (done) {
 		const channel = client.channel('messaging', '123');
 		expect(channel.cid).to.eql('messaging:123');