diff --git a/esphome/components/bluetooth_proxy/bluetooth_connection.cpp b/esphome/components/bluetooth_proxy/bluetooth_connection.cpp
index a4cf2d8481..8b5190a6bb 100644
--- a/esphome/components/bluetooth_proxy/bluetooth_connection.cpp
+++ b/esphome/components/bluetooth_proxy/bluetooth_connection.cpp
@@ -252,7 +252,7 @@ void BluetoothConnection::send_service_for_discovery_() {
 
     // Calculate the actual size of just this service
     api::ProtoSize service_sizer;
-    service.calculate_size(service_sizer);
+    service_resp.calculate_size(service_sizer);
     size_t service_size = service_sizer.get_size() + 1;  // +1 for field tag
 
     // Check if adding this service would exceed the limit