diff --git a/libraries/AP_Baro/AP_Baro_SITL.cpp b/libraries/AP_Baro/AP_Baro_SITL.cpp
index 9b41e33645..fc26899485 100644
--- a/libraries/AP_Baro/AP_Baro_SITL.cpp
+++ b/libraries/AP_Baro/AP_Baro_SITL.cpp
@@ -66,7 +66,11 @@ void AP_Baro_SITL::_timer()
         return;
     }
 
-    sim_alt += _sitl->baro[_instance].drift * now * 0.001f;
+    const auto drift_delta_t_ms = now - last_drift_delta_t_ms;
+    last_drift_delta_t_ms = now;
+    total_alt_drift += _sitl->baro[_instance].drift * drift_delta_t_ms * 0.001f;
+
+    sim_alt += total_alt_drift;
     sim_alt += _sitl->baro[_instance].noise * rand_float();
 
     // add baro glitch
diff --git a/libraries/AP_Baro/AP_Baro_SITL.h b/libraries/AP_Baro/AP_Baro_SITL.h
index 68ba04d016..7d724aeaeb 100644
--- a/libraries/AP_Baro/AP_Baro_SITL.h
+++ b/libraries/AP_Baro/AP_Baro_SITL.h
@@ -48,5 +48,7 @@ private:
     float _recent_press;
     float _last_altitude;
 
+    uint32_t last_drift_delta_t_ms;  // allows for integration of drift over time
+    float total_alt_drift;  // integrated altitude drift in metres
 };
 #endif  // AP_SIM_BARO_ENABLED