diff --git a/libraries/mbed/targets/hal/TARGET_NORDIC/TARGET_MCU_NRF51822/us_ticker.c b/libraries/mbed/targets/hal/TARGET_NORDIC/TARGET_MCU_NRF51822/us_ticker.c
index e8435afe42..d0da86d94c 100644
--- a/libraries/mbed/targets/hal/TARGET_NORDIC/TARGET_MCU_NRF51822/us_ticker.c
+++ b/libraries/mbed/targets/hal/TARGET_NORDIC/TARGET_MCU_NRF51822/us_ticker.c
@@ -188,15 +188,15 @@ void us_ticker_set_interrupt(timestamp_t timestamp)
     }
 
     uint32_t callbackTime = MICROSECONDS_TO_RTC_UNITS(timestamp);
-    if (us_ticker_callbackPending && (callbackTime == us_ticker_callbackTimestamp)) {
-        return;
-    }
     if (callbackTime == rtc1_getCounter()) {
         us_ticker_callbackPending = false;
         rtc1_disableCompareInterrupt();
         us_ticker_irq_handler();
         return;
     }
+    if (us_ticker_callbackPending && (callbackTime == us_ticker_callbackTimestamp)) {
+        return;
+    }
 
     NRF_RTC1->CC[0]             = callbackTime & MAX_RTC_COUNTER_VAL;
     us_ticker_callbackTimestamp = callbackTime;