diff --git a/extmod/moductypes.c b/extmod/moductypes.c
index cf83f43e3..62bbcbac2 100644
--- a/extmod/moductypes.c
+++ b/extmod/moductypes.c
@@ -558,7 +558,7 @@ STATIC mp_obj_t uctypes_struct_subscr(mp_obj_t self_in, mp_obj_t index_in, mp_ob
             uint val_type = GET_TYPE(arr_sz, VAL_TYPE_BITS);
             arr_sz &= VALUE_MASK(VAL_TYPE_BITS);
             if (index >= arr_sz) {
-                nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "struct: index out of range"));
+                mp_raise_msg(&mp_type_IndexError, "struct: index out of range");
             }
 
             if (t->len == 2) {
diff --git a/extmod/moduheapq.c b/extmod/moduheapq.c
index 1574eb862..f63305210 100644
--- a/extmod/moduheapq.c
+++ b/extmod/moduheapq.c
@@ -81,7 +81,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_uheapq_heappush_obj, mod_uheapq_heappush);
 STATIC mp_obj_t mod_uheapq_heappop(mp_obj_t heap_in) {
     mp_obj_list_t *heap = uheapq_get_heap(heap_in);
     if (heap->len == 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "empty heap"));
+        mp_raise_msg(&mp_type_IndexError, "empty heap");
     }
     mp_obj_t item = heap->items[0];
     heap->len -= 1;
diff --git a/extmod/modutimeq.c b/extmod/modutimeq.c
index 28a2a70c5..0183a0f4b 100644
--- a/extmod/modutimeq.c
+++ b/extmod/modutimeq.c
@@ -142,7 +142,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_utimeq_heappush_obj, 4, 4, mod_ut
 STATIC mp_obj_t mod_utimeq_heappop(mp_obj_t heap_in, mp_obj_t list_ref) {
     mp_obj_utimeq_t *heap = utimeq_get_heap(heap_in);
     if (heap->len == 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "empty heap"));
+        mp_raise_msg(&mp_type_IndexError, "empty heap");
     }
     mp_obj_list_t *ret = MP_OBJ_TO_PTR(list_ref);
     if (!mp_obj_is_type(list_ref, &mp_type_list) || ret->len < 3) {
@@ -167,7 +167,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_utimeq_heappop_obj, mod_utimeq_heappop);
 STATIC mp_obj_t mod_utimeq_peektime(mp_obj_t heap_in) {
     mp_obj_utimeq_t *heap = utimeq_get_heap(heap_in);
     if (heap->len == 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "empty heap"));
+        mp_raise_msg(&mp_type_IndexError, "empty heap");
     }
 
     struct qentry *item = &heap->items[0];
diff --git a/extmod/network_cyw43.c b/extmod/network_cyw43.c
index fe73b0715..45bb6163e 100644
--- a/extmod/network_cyw43.c
+++ b/extmod/network_cyw43.c
@@ -196,7 +196,7 @@ STATIC mp_obj_t network_cyw43_scan(size_t n_args, const mp_obj_t *pos_args, mp_m
     int scan_res = cyw43_wifi_scan(self->cyw, &opts, MP_OBJ_TO_PTR(res), network_cyw43_scan_cb);
 
     if (scan_res < 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "STA must be active"));
+        mp_raise_msg(&mp_type_OSError, "STA must be active");
     }
 
     // Wait for scan to finish, with a 10s timeout
diff --git a/extmod/vfs_posix_file.c b/extmod/vfs_posix_file.c
index 6f7ce814f..30fde818e 100644
--- a/extmod/vfs_posix_file.c
+++ b/extmod/vfs_posix_file.c
@@ -44,7 +44,7 @@ typedef struct _mp_obj_vfs_posix_file_t {
 #ifdef MICROPY_CPYTHON_COMPAT
 STATIC void check_fd_is_open(const mp_obj_vfs_posix_file_t *o) {
     if (o->fd < 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "I/O operation on closed file"));
+        mp_raise_msg(&mp_type_ValueError, "I/O operation on closed file");
     }
 }
 #else
diff --git a/ports/esp32/modesp32.c b/ports/esp32/modesp32.c
index ada881167..ddc030e3f 100644
--- a/ports/esp32/modesp32.c
+++ b/ports/esp32/modesp32.c
@@ -48,7 +48,7 @@ STATIC mp_obj_t esp32_wake_on_touch(const mp_obj_t wake) {
     if (machine_rtc_config.ext0_pin != -1) {
         mp_raise_ValueError("no resources");
     }
-     //nlr_raise(mp_obj_new_exception_msg(&mp_type_RuntimeError, "touchpad wakeup not available for this version of ESP-IDF"));
+    //mp_raise_msg(&mp_type_RuntimeError, "touchpad wakeup not available for this version of ESP-IDF");
 
     machine_rtc_config.wake_on_touch = mp_obj_is_true(wake);
     return mp_const_none;
@@ -74,7 +74,7 @@ STATIC mp_obj_t esp32_wake_on_ext0(size_t n_args, const mp_obj_t *pos_args, mp_m
         gpio_num_t pin_id = machine_pin_get_id(args[ARG_pin].u_obj);
         if (pin_id != machine_rtc_config.ext0_pin) {
             if (!RTC_IS_VALID_EXT_PIN(pin_id)) {
-                nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "invalid pin"));
+                mp_raise_msg(&mp_type_ValueError, "invalid pin");
             }
             machine_rtc_config.ext0_pin = pin_id;
         }
@@ -109,7 +109,7 @@ STATIC mp_obj_t esp32_wake_on_ext1(size_t n_args, const mp_obj_t *pos_args, mp_m
 
             gpio_num_t pin_id = machine_pin_get_id(elem[i]);
             if (!RTC_IS_VALID_EXT_PIN(pin_id)) {
-                nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "invalid pin"));
+                mp_raise_msg(&mp_type_ValueError, "invalid pin");
                 break;
             }
             ext1_pins |= (1ll << pin_id);
diff --git a/ports/esp32/modmachine.c b/ports/esp32/modmachine.c
index 0c803d096..e722ed2c5 100644
--- a/ports/esp32/modmachine.c
+++ b/ports/esp32/modmachine.c
@@ -119,7 +119,7 @@ STATIC mp_obj_t machine_sleep_helper(wake_type_t wake_type, size_t n_args, const
 
     if (machine_rtc_config.wake_on_touch) {
         if (esp_sleep_enable_touchpad_wakeup() != ESP_OK) {
-            nlr_raise(mp_obj_new_exception_msg(&mp_type_RuntimeError, "esp_sleep_enable_touchpad_wakeup() failed"));
+            mp_raise_msg(&mp_type_RuntimeError, "esp_sleep_enable_touchpad_wakeup() failed");
         }
     }
 
diff --git a/ports/esp32/modnetwork.c b/ports/esp32/modnetwork.c
index 012dc5bce..ba967b8cb 100644
--- a/ports/esp32/modnetwork.c
+++ b/ports/esp32/modnetwork.c
@@ -233,7 +233,7 @@ static esp_err_t event_handler(void *ctx, system_event_t *event) {
 
 /*void error_check(bool status, const char *msg) {
     if (!status) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, msg));
+        mp_raise_msg(&mp_type_OSError, msg);
     }
 }
 */
@@ -441,7 +441,7 @@ STATIC mp_obj_t esp_scan(mp_obj_t self_in) {
     wifi_mode_t mode;
     ESP_EXCEPTIONS(esp_wifi_get_mode(&mode));
     if ((mode & WIFI_MODE_STA) == 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "STA must be active"));
+        mp_raise_msg(&mp_type_OSError, "STA must be active");
     }
 
     mp_obj_t list = mp_obj_new_list(0, NULL);
diff --git a/ports/esp32/mpthreadport.c b/ports/esp32/mpthreadport.c
index 1c0d889e9..d7db0ff61 100644
--- a/ports/esp32/mpthreadport.c
+++ b/ports/esp32/mpthreadport.c
@@ -27,6 +27,7 @@
 
 #include "stdio.h"
 
+#include "py/runtime.h"
 #include "py/gc.h"
 #include "py/mpthread.h"
 #include "py/mphal.h"
@@ -135,7 +136,7 @@ void mp_thread_create_ex(void *(*entry)(void*), void *arg, size_t *stack_size, i
     BaseType_t result = xTaskCreatePinnedToCore(freertos_entry, name, *stack_size / sizeof(StackType_t), arg, priority, &th->id, MP_TASK_COREID);
     if (result != pdPASS) {
         mp_thread_mutex_unlock(&thread_mutex);
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "can't create thread"));
+        mp_raise_msg(&mp_type_OSError, "can't create thread");
     }
 
     // adjust the stack_size to provide room to recover from hitting the limit
diff --git a/ports/esp8266/esp_mphal.c b/ports/esp8266/esp_mphal.c
index 2ce288ea3..25201425b 100644
--- a/ports/esp8266/esp_mphal.c
+++ b/ports/esp8266/esp_mphal.c
@@ -149,8 +149,7 @@ void ets_event_poll(void) {
 
 void __assert_func(const char *file, int line, const char *func, const char *expr) {
     printf("assert:%s:%d:%s: %s\n", file, line, func, expr);
-    nlr_raise(mp_obj_new_exception_msg(&mp_type_AssertionError,
-        "C-level assert"));
+    mp_raise_msg(&mp_type_AssertionError, "C-level assert");
 }
 
 void mp_hal_signal_input(void) {
diff --git a/ports/esp8266/machine_pin.c b/ports/esp8266/machine_pin.c
index 14505c8f0..1200aa9de 100644
--- a/ports/esp8266/machine_pin.c
+++ b/ports/esp8266/machine_pin.c
@@ -384,7 +384,7 @@ STATIC mp_obj_t pyb_pin_irq(size_t n_args, const mp_obj_t *pos_args, mp_map_t *k
     mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
 
     if (self->phys_port >= 16) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "pin does not have IRQ capabilities"));
+        mp_raise_msg(&mp_type_OSError, "pin does not have IRQ capabilities");
     }
 
     if (n_args > 1 || kw_args->used != 0) {
diff --git a/ports/esp8266/modesp.c b/ports/esp8266/modesp.c
index 6c9fa9e13..2aeb3d690 100644
--- a/ports/esp8266/modesp.c
+++ b/ports/esp8266/modesp.c
@@ -43,7 +43,7 @@
 
 void error_check(bool status, const char *msg) {
     if (!status) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, msg));
+        mp_raise_msg(&mp_type_OSError, msg);
     }
 }
 
diff --git a/ports/esp8266/modnetwork.c b/ports/esp8266/modnetwork.c
index c58aae1cb..6bdbe6e23 100644
--- a/ports/esp8266/modnetwork.c
+++ b/ports/esp8266/modnetwork.c
@@ -229,8 +229,7 @@ STATIC void esp_scan_cb(void *result, STATUS status) {
 STATIC mp_obj_t esp_scan(mp_obj_t self_in) {
     require_if(self_in, STATION_IF);
     if ((wifi_get_opmode() & STATION_MODE) == 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError,
-            "STA must be active"));
+        mp_raise_msg(&mp_type_OSError, "STA must be active");
     }
     mp_obj_t list = mp_obj_new_list(0, NULL);
     esp_scan_list = &list;
@@ -247,7 +246,7 @@ STATIC mp_obj_t esp_scan(mp_obj_t self_in) {
         ets_loop_iter();
     }
     if (list == MP_OBJ_NULL) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "scan failed"));
+        mp_raise_msg(&mp_type_OSError, "scan failed");
     }
     return list;
 }
@@ -313,8 +312,7 @@ STATIC mp_obj_t esp_ifconfig(size_t n_args, const mp_obj_t *args) {
             wifi_softap_dhcps_stop();
         }
         if (!wifi_set_ip_info(self->if_id, &info)) {
-          nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError,
-            "wifi_set_ip_info() failed"));
+          mp_raise_msg(&mp_type_OSError, "wifi_set_ip_info() failed");
         }
         dns_setserver(0, &dns_addr);
         if (restart_dhcp_server) {
diff --git a/ports/nrf/boards/microbit/modules/microbitimage.c b/ports/nrf/boards/microbit/modules/microbitimage.c
index fca507508..ce4a959f0 100644
--- a/ports/nrf/boards/microbit/modules/microbitimage.c
+++ b/ports/nrf/boards/microbit/modules/microbitimage.c
@@ -227,8 +227,7 @@ STATIC mp_obj_t microbit_image_make_new(const mp_obj_type_t *type_in, mp_uint_t
                     return image_from_parsed_str(str, len);
                 }
             } else {
-                nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError,
-                    "Image(s) takes a string."));
+                mp_raise_msg(&mp_type_TypeError, "Image(s) takes a string.");
             }
         }
 
@@ -259,8 +258,7 @@ STATIC mp_obj_t microbit_image_make_new(const mp_obj_type_t *type_in, mp_uint_t
         }
 
         default: {
-            nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError,
-                "Image() takes 0 to 3 arguments"));
+            mp_raise_msg(&mp_type_TypeError, "Image() takes 0 to 3 arguments");
         }
     }
 }
@@ -365,7 +363,7 @@ MP_DEFINE_CONST_FUN_OBJ_3(microbit_image_get_pixel_obj, microbit_image_get_pixel
 /* Raise an exception if not mutable */
 static void check_mutability(microbit_image_obj_t *self) {
     if (self->base.five) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "image cannot be modified (try copying first)"));
+        mp_raise_msg(&mp_type_TypeError, "image cannot be modified (try copying first)");
     }
 }
 
@@ -408,11 +406,10 @@ mp_obj_t microbit_image_blit(mp_uint_t n_args, const mp_obj_t *args) {
 
     mp_obj_t src = args[1];
     if (mp_obj_get_type(src) != &microbit_image_type) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "expecting an image"));
+        mp_raise_msg(&mp_type_TypeError, "expecting an image");
     }
     if (n_args == 7) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError,
-            "must specify both offsets"));
+        mp_raise_msg(&mp_type_TypeError, "must specify both offsets");
     }
     mp_int_t x = mp_obj_get_int(args[2]);
     mp_int_t y = mp_obj_get_int(args[3]);
diff --git a/ports/stm32/modnetwork.c b/ports/stm32/modnetwork.c
index 19a60103f..4b0f77f9a 100644
--- a/ports/stm32/modnetwork.c
+++ b/ports/stm32/modnetwork.c
@@ -119,7 +119,7 @@ mp_obj_t mod_network_find_nic(const uint8_t *ip) {
         return nic;
     }
 
-    nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "no available NIC"));
+    mp_raise_msg(&mp_type_OSError, "no available NIC");
 }
 
 STATIC mp_obj_t network_route(void) {
diff --git a/ports/stm32/modnwcc3k.c b/ports/stm32/modnwcc3k.c
index 8723994f4..b3fd93922 100644
--- a/ports/stm32/modnwcc3k.c
+++ b/ports/stm32/modnwcc3k.c
@@ -443,7 +443,7 @@ STATIC mp_obj_t cc3k_make_new(const mp_obj_type_t *type, size_t n_args, size_t n
             ReadWlanInterruptPin, SpiResumeSpi, SpiPauseSpi, WriteWlanPin);
 
     if (wlan_start(0) != 0) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "failed to init CC3000 module"));
+        mp_raise_msg(&mp_type_OSError, "failed to init CC3000 module");
     }
 
     // set connection policy. this should be called explicitly by the user
diff --git a/ports/stm32/modusocket.c b/ports/stm32/modusocket.c
index 5a1633113..46d7240ca 100644
--- a/ports/stm32/modusocket.c
+++ b/ports/stm32/modusocket.c
@@ -425,7 +425,7 @@ STATIC mp_obj_t mod_usocket_getaddrinfo(mp_obj_t host_in, mp_obj_t port_in) {
     }
 
     if (!have_ip) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "no available NIC"));
+        mp_raise_msg(&mp_type_OSError, "no available NIC");
     }
 
     mp_obj_tuple_t *tuple = MP_OBJ_TO_PTR(mp_obj_new_tuple(5, NULL));
diff --git a/ports/stm32/mpthreadport.c b/ports/stm32/mpthreadport.c
index 7b3b92934..0077e1393 100644
--- a/ports/stm32/mpthreadport.c
+++ b/ports/stm32/mpthreadport.c
@@ -75,7 +75,7 @@ void mp_thread_create(void *(*entry)(void*), void *arg, size_t *stack_size) {
     uint32_t id = pyb_thread_new(th, stack, stack_len, entry, arg);
     if (id == 0) {
         mp_thread_mutex_unlock(&thread_mutex);
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "can't create thread"));
+        mp_raise_msg(&mp_type_OSError, "can't create thread");
     }
 
     mp_thread_mutex_unlock(&thread_mutex);
diff --git a/py/objint.c b/py/objint.c
index 6473767e4..2fdcf5864 100644
--- a/py/objint.c
+++ b/py/objint.c
@@ -137,7 +137,7 @@ STATIC mp_fp_as_int_class_t mp_classify_fp_as_int(mp_float_t val) {
 mp_obj_t mp_obj_new_int_from_float(mp_float_t val) {
     int cl = fpclassify(val);
     if (cl == FP_INFINITE) {
-        nlr_raise(mp_obj_new_exception_msg(&mp_type_OverflowError, "can't convert inf to int"));
+        mp_raise_msg(&mp_type_OverflowError, "can't convert inf to int");
     } else if (cl == FP_NAN) {
         mp_raise_ValueError("can't convert NaN to int");
     } else {