diff --git a/Source/portable/GCC/ARM_CM3/port.c b/Source/portable/GCC/ARM_CM3/port.c
index cc3568fde..eb0e03340 100644
--- a/Source/portable/GCC/ARM_CM3/port.c
+++ b/Source/portable/GCC/ARM_CM3/port.c
@@ -276,7 +276,7 @@ void xPortSysTickHandler( void )
 void prvSetupTimerInterrupt( void )
 {
 	/* Configure SysTick to interrupt at the requested rate. */
-	*(portNVIC_SYSTICK_LOAD) = configCPU_CLOCK_HZ / configTICK_RATE_HZ;
+	*(portNVIC_SYSTICK_LOAD) = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) - 1UL;
 	*(portNVIC_SYSTICK_CTRL) = portNVIC_SYSTICK_CLK | portNVIC_SYSTICK_INT | portNVIC_SYSTICK_ENABLE;
 }
 /*-----------------------------------------------------------*/