diff --git a/hal/targets/hal/TARGET_STM/TARGET_STM32F1/rtc_api.c b/hal/targets/hal/TARGET_STM/TARGET_STM32F1/rtc_api.c
index 50cb7286f5..f2b15f2e98 100644
--- a/hal/targets/hal/TARGET_STM/TARGET_STM32F1/rtc_api.c
+++ b/hal/targets/hal/TARGET_STM/TARGET_STM32F1/rtc_api.c
@@ -163,6 +163,8 @@ time_t rtc_read(void)
     timeinfo.tm_hour = timeStruct.Hours;
     timeinfo.tm_min  = timeStruct.Minutes;
     timeinfo.tm_sec  = timeStruct.Seconds;
+    // Daylight Saving Time information is not available
+    timeinfo.tm_isdst  = -1;
 
     // Convert to timestamp
     time_t t = mktime(&timeinfo);
diff --git a/hal/targets/hal/TARGET_STM/TARGET_STM32F3/rtc_api.c b/hal/targets/hal/TARGET_STM/TARGET_STM32F3/rtc_api.c
index 838eb4083c..f49eb05025 100644
--- a/hal/targets/hal/TARGET_STM/TARGET_STM32F3/rtc_api.c
+++ b/hal/targets/hal/TARGET_STM/TARGET_STM32F3/rtc_api.c
@@ -182,6 +182,8 @@ time_t rtc_read(void)
     timeinfo.tm_hour = timeStruct.Hours;
     timeinfo.tm_min  = timeStruct.Minutes;
     timeinfo.tm_sec  = timeStruct.Seconds;
+    // Daylight Saving Time information is not available
+    timeinfo.tm_isdst  = -1;
 
     // Convert to timestamp
     time_t t = mktime(&timeinfo);
diff --git a/hal/targets/hal/TARGET_STM/TARGET_STM32F4/rtc_api.c b/hal/targets/hal/TARGET_STM/TARGET_STM32F4/rtc_api.c
index 2f40051381..5506e3ea35 100644
--- a/hal/targets/hal/TARGET_STM/TARGET_STM32F4/rtc_api.c
+++ b/hal/targets/hal/TARGET_STM/TARGET_STM32F4/rtc_api.c
@@ -182,6 +182,8 @@ time_t rtc_read(void)
     timeinfo.tm_hour = timeStruct.Hours;
     timeinfo.tm_min  = timeStruct.Minutes;
     timeinfo.tm_sec  = timeStruct.Seconds;
+    // Daylight Saving Time information is not available
+    timeinfo.tm_isdst  = -1;
 
     // Convert to timestamp
     time_t t = mktime(&timeinfo);
diff --git a/hal/targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c b/hal/targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c
index 2293faba5e..c7d4ba36c2 100644
--- a/hal/targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c
+++ b/hal/targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c
@@ -182,6 +182,8 @@ time_t rtc_read(void)
     timeinfo.tm_hour = timeStruct.Hours;
     timeinfo.tm_min  = timeStruct.Minutes;
     timeinfo.tm_sec  = timeStruct.Seconds;
+    // Daylight Saving Time information is not available
+    timeinfo.tm_isdst  = -1;
 
     // Convert to timestamp
     time_t t = mktime(&timeinfo);