On 29 August 1942, "Mackay" was temporarily detached to the Home Fleet in support of the Arctic convoy PQ 18 to Northern Russia and the return convoy QP 14. "Mackay" formed part of the distant cover force (led by the battleships and ) for PQ 18 and QP 14, before returning to Harwich on 27 September 1942. On 21 December, "Mackay" was again detached to carry out screening operations with the Home Fleet, to cover for more modern destroyers that were deployed elsewhere. "Mackay" returned to Harwich on 26 December.