You can also pick up a Home Mini on its own for as low as £27.99 from MyMemory, saving you nearly £22.
Spotify's Premium for Family subscription, which works for up to 6 people sharing the same UK address costs £14.99. This is five pounds more than the normal Premium account for individuals, which costs £9.99 per month or £119.88 annually. The Google Home Mini promotion on the Premium for Family plan ends 14 May 2019, and has to be claimed by 24 May 2019.
Separately, students interested in a the Premium plan for individuals can get 50% off, paying only £4.99 per month.