diff --git a/plugins/chat/app/services/chat/lookup_channel_threads.rb b/plugins/chat/app/services/chat/lookup_channel_threads.rb
index 3622b0e4aeb..352498b4a49 100644
--- a/plugins/chat/app/services/chat/lookup_channel_threads.rb
+++ b/plugins/chat/app/services/chat/lookup_channel_threads.rb
@@ -84,24 +84,26 @@ module Chat
 
       threads = unread_threads + read_threads
 
-      last_replies =
-        Chat::Message
-          .strict_loading
-          .includes(:user, :uploads)
-          .from(<<~SQL)
-            (
-              SELECT thread_id, MAX(created_at) AS latest_created_at, MAX(id) AS latest_message_id
-              FROM chat_messages
-              WHERE thread_id IN (#{threads.map(&:id).join(",")})
-              GROUP BY thread_id
-            ) AS last_replies_subquery
-          SQL
-          .joins(
-            "INNER JOIN chat_messages ON chat_messages.id = last_replies_subquery.latest_message_id",
-          )
-          .index_by(&:thread_id)
+      if threads.present?
+        last_replies =
+          Chat::Message
+            .strict_loading
+            .includes(:user, :uploads)
+            .from(<<~SQL)
+              (
+                SELECT thread_id, MAX(created_at) AS latest_created_at, MAX(id) AS latest_message_id
+                FROM chat_messages
+                WHERE thread_id IN (#{threads.map(&:id).join(",")})
+                GROUP BY thread_id
+              ) AS last_replies_subquery
+            SQL
+            .joins(
+              "INNER JOIN chat_messages ON chat_messages.id = last_replies_subquery.latest_message_id",
+            )
+            .index_by(&:thread_id)
 
-      threads.each { |thread| thread.last_reply = last_replies[thread.id] }
+        threads.each { |thread| thread.last_reply = last_replies[thread.id] }
+      end
 
       threads
     end
diff --git a/plugins/chat/spec/services/chat/lookup_channel_threads_spec.rb b/plugins/chat/spec/services/chat/lookup_channel_threads_spec.rb
index cda03e1c25f..f724565e1c3 100644
--- a/plugins/chat/spec/services/chat/lookup_channel_threads_spec.rb
+++ b/plugins/chat/spec/services/chat/lookup_channel_threads_spec.rb
@@ -10,6 +10,7 @@ RSpec.describe Chat::LookupChannelThreads do
 
     fab!(:current_user) { Fabricate(:user) }
     fab!(:channel) { Fabricate(:chat_channel, threading_enabled: true) }
+    fab!(:channel_with_no_threads) { Fabricate(:chat_channel, threading_enabled: true) }
     fab!(:thread_1) { Fabricate(:chat_thread, channel: channel) }
     fab!(:thread_2) { Fabricate(:chat_thread, channel: channel) }
     fab!(:thread_3) { Fabricate(:chat_thread, channel: channel) }
@@ -32,6 +33,12 @@ RSpec.describe Chat::LookupChannelThreads do
         end
       end
 
+      it "does not return any threads when a channel has no threads" do
+        expect(
+          described_class.call(channel_id: channel_with_no_threads.id, guardian:).threads,
+        ).to eq([])
+      end
+
       context "when all steps pass" do
         before do
           msg_1 =