Brexit sees M&S lose £16.1m due to tariffs as well as admin and supply chain costs Do you have news? Tell us about it! 3k British retailer Marks and Spencer has revealed that Brexit cost the company over £16 million in tariffs, administration and supply chain expenses during the 52 weeks up to 27th March 2021. The long-established supermarket and clothing chain published the figures as part of its annual financial results document, titled âNever The Same Again – Forging A Reshaped M&Sâ. M&S said the following estimated cost impacts were incurred by the Group in 2020/21 as a result of Brexit: