diff --git a/py/mpconfig.h b/py/mpconfig.h
index 58aa2ce0c0..6de184a9c4 100644
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -909,9 +909,8 @@ typedef double mp_float_t;
 #define UINT_FMT "%lu"
 #define INT_FMT "%ld"
 #elif defined(_WIN64)
-#include <inttypes.h>
-#define UINT_FMT "%"PRIu64
-#define INT_FMT "%"PRId64
+#define UINT_FMT "%llu"
+#define INT_FMT "%lld"
 #else
 // Archs where mp_int_t == int
 #define UINT_FMT "%u"
diff --git a/py/mpprint.c b/py/mpprint.c
index 30bbe3c6d9..19575f8a8a 100644
--- a/py/mpprint.c
+++ b/py/mpprint.c
@@ -529,7 +529,7 @@ int mp_vprintf(const mp_print_t *print, const char *fmt, va_list args) {
             // Because 'l' is eaten above, another 'l' means %ll.  We need to support
             // this length specifier for OBJ_REPR_D (64-bit NaN boxing).
             // TODO Either enable this unconditionally, or provide a specific config var.
-            #if MICROPY_OBJ_REPR == MICROPY_OBJ_REPR_D
+            #if (MICROPY_OBJ_REPR == MICROPY_OBJ_REPR_D) || defined(_WIN64)
             case 'l': {
                 unsigned long long int arg_value = va_arg(args, unsigned long long int);
                 ++fmt;