diff --git a/drivers/include/periph/rtc.h b/drivers/include/periph/rtc.h
index 016e922b06..7c87c91e7d 100644
--- a/drivers/include/periph/rtc.h
+++ b/drivers/include/periph/rtc.h
@@ -131,6 +131,22 @@ void rtc_poweroff(void);
  */
 void rtc_tm_normalize(struct tm *time);
 
+/**
+ * @brief Compare two time structs.
+ *
+ * @pre   The time structs @p a and @p b are assumed to be normalized.
+ *        Use @ref rtc_tm_normalize to normalize a struct tm that has been
+ *        manually edited.
+ *
+ * @param[in] a       The first time struct.
+ * @param[in] b       The second time struct.
+ *
+ * @return an integer < 0 if a is earlier than b
+ * @return an integer > 0 if a is later than b
+ * @return              0 if a and b are equal
+ */
+int rtc_tm_compare(const struct tm *a, const struct tm *b);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/drivers/periph_common/rtc.c b/drivers/periph_common/rtc.c
index 551bcd6e39..e2a5dc74fd 100644
--- a/drivers/periph_common/rtc.c
+++ b/drivers/periph_common/rtc.c
@@ -147,3 +147,20 @@ void rtc_tm_normalize(struct tm *t)
     t->tm_wday = _wday(t->tm_mday, t->tm_mon, t->tm_year + 1900);
 #endif
 }
+
+#define RETURN_IF_DIFFERENT(a, b, member)   \
+    if (a->member != b->member) {           \
+        return a->member-b->member;         \
+    }
+
+int rtc_tm_compare(const struct tm *a, const struct tm *b)
+{
+    RETURN_IF_DIFFERENT(a, b, tm_year);
+    RETURN_IF_DIFFERENT(a, b, tm_mon);
+    RETURN_IF_DIFFERENT(a, b, tm_mday);
+    RETURN_IF_DIFFERENT(a, b, tm_hour);
+    RETURN_IF_DIFFERENT(a, b, tm_min);
+    RETURN_IF_DIFFERENT(a, b, tm_sec);
+
+    return 0;
+}