A so-called Tesco tax on large retailers starts in Northern Ireland this weekend.
The levy to subsidise rates relief for small businesses has been criticised by Sainsbury's chief executive Justin King, among others, amid arguments that it unfairly targets the supermarket sector and could limit investment and cost jobs.
The Northern Ireland Retail Consortium, which represents large retailers, has said the levy is unfair and poses a risk to future investment. Ikea has said it could put hundreds of jobs at risk.
But the finance minister at Stormont, Sammy Wilson, said it represents a minuscule proportion of the giant retailers' profits.
The charge will affect 76 large shops and raise £5m to fund a rates cut for small shops.
The levy will be made at a rate of 15%, not 20% as originally planned.
The tax is introduced on 1 April.