Found 6th Feb 2016
Groupon are offering 6 months subscription for a Birchbox for £29.95, plus £9.95 for the delivery for all six. Normal price is £60 for six months subscription plus £2.95 per each box for delivery, saving £37.80! THEN Topcashback are offering £7.35 back for signing up to 6 months, which seems to have worked in conjunction with the Groupon offer! The whole 6 months subscription costs just £32.55.