diff --git a/drivers/serial/uart_nrfx_uart.c b/drivers/serial/uart_nrfx_uart.c
index a1751d713b..b9eb254ed7 100644
--- a/drivers/serial/uart_nrfx_uart.c
+++ b/drivers/serial/uart_nrfx_uart.c
@@ -82,7 +82,7 @@ static struct {
 	size_t tx_buffer_length;
 	volatile size_t tx_counter;
 #if HW_FLOW_CONTROL_AVAILABLE
-	s32_t tx_timeout;
+	int32_t tx_timeout;
 	struct k_delayed_work tx_timeout_work;
 #endif
 } uart0_cb;