diff --git a/targets/TARGET_STM/TARGET_STM32L4/flash_api.c b/targets/TARGET_STM/TARGET_STM32L4/flash_api.c
index 534894f08a..826e15e696 100644
--- a/targets/TARGET_STM/TARGET_STM32L4/flash_api.c
+++ b/targets/TARGET_STM/TARGET_STM32L4/flash_api.c
@@ -205,7 +205,7 @@ int32_t flash_program_page(flash_t *obj, uint32_t address,
 
     /*  HW needs an aligned address to program flash, which data
      *  parameters doesn't ensure  */
-    if ((uint32_t) data % 4 != 0) {
+    if ((uint32_t) data % 8 != 0) {
         volatile uint64_t data64;
         while ((address < (StartAddress + size)) && (status == 0)) {
             for (uint8_t i = 0; i < 8; i++) {
diff --git a/targets/TARGET_STM/TARGET_STM32WB/flash_api.c b/targets/TARGET_STM/TARGET_STM32WB/flash_api.c
index 3be8ad9248..8e708724d8 100644
--- a/targets/TARGET_STM/TARGET_STM32WB/flash_api.c
+++ b/targets/TARGET_STM/TARGET_STM32WB/flash_api.c
@@ -154,7 +154,7 @@ int32_t flash_program_page(flash_t *obj, uint32_t address, const uint8_t *data,
     StartAddress = address;
 
     /*  HW needs an aligned address to program flash, which data parameters doesn't ensure */
-    if ((uint32_t) data % 4 != 0) { // Data is not aligned, copy data in a temp buffer before programming it
+    if ((uint32_t) data % 8 != 0) { // Data is not aligned, copy data in a temp buffer before programming it
         volatile uint64_t data64;
         while ((address < (StartAddress + size)) && (status == 0)) {
             for (uint8_t i = 0; i < 8; i++) {