diff --git a/src/drivers/gps/gps.cpp b/src/drivers/gps/gps.cpp
index 004be4cc8b90..e35d3f5598f9 100644
--- a/src/drivers/gps/gps.cpp
+++ b/src/drivers/gps/gps.cpp
@@ -475,6 +475,9 @@ int GPS::pollOrRead(uint8_t *buf, size_t buf_length, int timeout)
 
 	if (_interface == GPSHelper::Interface::UART) {
 		ret = _uart.readAtLeast(buf, buf_length, math::min(character_count, buf_length), timeout_adjusted);
+		if (ret > 0) {
+			_num_bytes_read += ret;
+		}
 
 // SPI is only supported on LInux
 #if defined(__PX4_LINUX)