diff --git a/include/modbus/modbus_rtu.h b/include/modbus/modbus_rtu.h
index cbe1136d873..6eb24da98d5 100644
--- a/include/modbus/modbus_rtu.h
+++ b/include/modbus/modbus_rtu.h
@@ -334,6 +334,18 @@ struct mbs_rtu_user_callbacks {
 	int (*holding_reg_wr_fp)(uint16_t addr, float reg);
 };
 
+/**
+ * @brief Get Modbus RTU interface index according to interface name
+ *
+ * If there is more than one interface, it can be used to clearly
+ * identify interfaces in the application.
+ *
+ * @param iface_name Modbus RTU interface name
+ *
+ * @retval           Modbus RTU interface index or negative error value.
+ */
+int mb_rtu_iface_get_by_name(const char *iface_name);
+
 /**
  * @brief Configure Modbus Interface as server
  *
diff --git a/samples/subsys/modbus/rtu_client/app.overlay b/samples/subsys/modbus/rtu_client/app.overlay
index 124708a18c3..39f4489fc23 100644
--- a/samples/subsys/modbus/rtu_client/app.overlay
+++ b/samples/subsys/modbus/rtu_client/app.overlay
@@ -9,7 +9,7 @@
 
 	modbus0 {
 		compatible = "zephyr,modbus-serial";
-		label = "MODBUS";
+		label = "MODBUS0";
 		status = "okay";
 		de-gpios = <&arduino_header 15 GPIO_ACTIVE_LOW>;	/* D9 */
 	};
diff --git a/samples/subsys/modbus/rtu_server/app.overlay b/samples/subsys/modbus/rtu_server/app.overlay
index 124708a18c3..39f4489fc23 100644
--- a/samples/subsys/modbus/rtu_server/app.overlay
+++ b/samples/subsys/modbus/rtu_server/app.overlay
@@ -9,7 +9,7 @@
 
 	modbus0 {
 		compatible = "zephyr,modbus-serial";
-		label = "MODBUS";
+		label = "MODBUS0";
 		status = "okay";
 		de-gpios = <&arduino_header 15 GPIO_ACTIVE_LOW>;	/* D9 */
 	};
diff --git a/samples/subsys/modbus/rtu_server/src/main.c b/samples/subsys/modbus/rtu_server/src/main.c
index 2e9052eaf3c..f746d088e26 100644
--- a/samples/subsys/modbus/rtu_server/src/main.c
+++ b/samples/subsys/modbus/rtu_server/src/main.c
@@ -102,8 +102,16 @@ static struct mbs_rtu_user_callbacks mbs_cbs = {
 
 static int init_modbus_server(void)
 {
-	const uint8_t iface = 0;
 	const uint32_t mb_rtu_br = 19200;
+	const char iface_name[] = {DT_PROP(DT_INST(0, zephyr_modbus_serial), label)};
+	int iface;
+
+	iface = mb_rtu_iface_get_by_name(iface_name);
+
+	if (iface < 0) {
+		LOG_ERR("Failed to get iface index for %s", iface_name);
+		return iface;
+	}
 
 	return mb_rtu_cfg_server(iface, 1, mb_rtu_br, UART_CFG_PARITY_NONE,
 				 &mbs_cbs, false);
diff --git a/subsys/modbus/mb_rtu_core.c b/subsys/modbus/mb_rtu_core.c
index 1c21da7d1a8..0339b4f2fbb 100644
--- a/subsys/modbus/mb_rtu_core.c
+++ b/subsys/modbus/mb_rtu_core.c
@@ -49,6 +49,7 @@ DT_INST_FOREACH_STATUS_OKAY(MB_RTU_DEFINE_GPIO_CFGS)
 		    (&d##_cfg_##n), (NULL))
 
 #define MODBUS_DT_GET_DEV(n) {					\
+		.iface_name = DT_INST_LABEL(n),			\
 		.dev_name = DT_INST_BUS_LABEL(n),		\
 		.de = MB_RTU_ASSIGN_GPIO_CFG(n, de_gpios),	\
 		.re = MB_RTU_ASSIGN_GPIO_CFG(n, re_gpios),	\
@@ -663,6 +664,7 @@ static struct mb_rtu_context *mb_cfg_iface(const uint8_t iface,
 
 	k_timer_init(&ctx->rtu_timer, mb_rtu_tmr_handler, NULL);
 	k_timer_user_data_set(&ctx->rtu_timer, ctx);
+	LOG_DBG("Modbus interface %s initialized", ctx->iface_name);
 
 	return ctx;
 }
@@ -696,6 +698,17 @@ int mb_rtu_cfg_server(const uint8_t iface, const uint8_t node_addr,
 	return 0;
 }
 
+int mb_rtu_iface_get_by_name(const char *iface_name)
+{
+	for (int i = 0; i < ARRAY_SIZE(mb_ctx_tbl); i++) {
+		if (strcmp(iface_name, mb_ctx_tbl[i].iface_name) == 0) {
+			return i;
+		}
+	}
+
+	return -ENODEV;
+}
+
 int mb_rtu_cfg_client(const uint8_t iface,
 		      const uint32_t baud, const enum uart_config_parity parity,
 		      const uint32_t rx_timeout,
diff --git a/subsys/modbus/mb_rtu_internal.h b/subsys/modbus/mb_rtu_internal.h
index 4d65c0e97dc..834b74676b0 100644
--- a/subsys/modbus/mb_rtu_internal.h
+++ b/subsys/modbus/mb_rtu_internal.h
@@ -89,6 +89,8 @@ struct mb_rtu_gpio_config {
 #define MB_RTU_STATE_CONFIGURED		0
 
 struct mb_rtu_context {
+	/* Interface name */
+	const char *iface_name;
 	/* UART device name */
 	const char *dev_name;
 	/* UART device */
diff --git a/tests/subsys/modbus_rtu/boards/frdm_k64f.overlay b/tests/subsys/modbus_rtu/boards/frdm_k64f.overlay
index 581336fe344..e439d4cee07 100644
--- a/tests/subsys/modbus_rtu/boards/frdm_k64f.overlay
+++ b/tests/subsys/modbus_rtu/boards/frdm_k64f.overlay
@@ -9,7 +9,7 @@
 
 	modbus0 {
 		compatible = "zephyr,modbus-serial";
-		label = "MODBUS";
+		label = "MODBUS0";
 		status = "okay";
 		de-gpios = <&gpiob 22 GPIO_ACTIVE_LOW>;	/* red LED */
 		re-gpios = <&gpioe 26 GPIO_ACTIVE_LOW>;	/* green LED */
@@ -22,7 +22,7 @@
 
 	modbus1 {
 		compatible = "zephyr,modbus-serial";
-		label = "MODBUS";
+		label = "MODBUS1";
 		status = "okay";
 	};
 };
diff --git a/tests/subsys/modbus_rtu/boards/reel_board.overlay b/tests/subsys/modbus_rtu/boards/reel_board.overlay
index 840434e4917..d5f6a80fae6 100644
--- a/tests/subsys/modbus_rtu/boards/reel_board.overlay
+++ b/tests/subsys/modbus_rtu/boards/reel_board.overlay
@@ -9,7 +9,7 @@
 
 	modbus0 {
 		compatible = "zephyr,modbus-serial";
-		label = "MODBUS";
+		label = "MODBUS0";
 		status = "okay";
 	};
 };