diff --git a/src/libmodbus/modbus.c b/src/libmodbus/modbus.c
index 17e36e1..5f4e1d4 100644
--- a/src/libmodbus/modbus.c
+++ b/src/libmodbus/modbus.c
@@ -1393,7 +1393,7 @@ int modbus_write_bits(modbus_t *ctx, int addr, int nb, const uint8_t *src)
     }
 
     rc = send_msg(ctx, req, req_length);
-    if (rc > 0) {
+    if (rc > 0 && ctx->slave != 0) {
         uint8_t rsp[MAX_MESSAGE_LENGTH];
 
         rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION);
@@ -1443,7 +1443,7 @@ int modbus_write_registers(modbus_t *ctx, int addr, int nb, const uint16_t *src)
     }
 
     rc = send_msg(ctx, req, req_length);
-    if (rc > 0) {
+    if (rc > 0 && ctx->slave != 0) {
         uint8_t rsp[MAX_MESSAGE_LENGTH];
 
         rc = _modbus_receive_msg(ctx, rsp, MSG_CONFIRMATION);