diff --git a/ports/nrf/drivers/flash.h b/ports/nrf/drivers/flash.h
index 0b341c39a4..7e6fff37a9 100644
--- a/ports/nrf/drivers/flash.h
+++ b/ports/nrf/drivers/flash.h
@@ -38,7 +38,7 @@
 #error Unknown chip
 #endif
 
-#define FLASH_IS_PAGE_ALIGNED(addr) ((uint32_t)(addr) & (FLASH_PAGESIZE - 1))
+#define FLASH_IS_PAGE_ALIGNED(addr) (((uint32_t)(addr) & (FLASH_PAGESIZE - 1)) == 0)
 
 #if BLUETOOTH_SD