diff --git a/portable/MPLAB/PIC24_dsPIC/portmacro.h b/portable/MPLAB/PIC24_dsPIC/portmacro.h
index 223e4936b..0974bc33b 100644
--- a/portable/MPLAB/PIC24_dsPIC/portmacro.h
+++ b/portable/MPLAB/PIC24_dsPIC/portmacro.h
@@ -59,6 +59,9 @@ typedef unsigned short UBaseType_t;
 #if( configUSE_16_BIT_TICKS == 1 )
 	typedef uint16_t TickType_t;
 	#define portMAX_DELAY ( TickType_t ) 0xffff
+/* 16-bit tick type on a 16-bit architecture, so reads of the tick count do
+ * not need to be guarded with a critical section. */
+	#define portTICK_TYPE_IS_ATOMIC 1
 #else
 	typedef uint32_t TickType_t;
 	#define portMAX_DELAY ( TickType_t ) 0xffffffffUL