The Competition and Markets Authority proposed on 7 August 2026 that Aldi, Lidl GB and Lidl NI be covered by the Groceries Market Investigation (Controlled Land) Order 2010, which already applies to Asda, Co-op, Marks and Spencer, Morrisons, Sainsbury's, Tesco and Waitrose. The order is intended to stop large grocery retailers using land agreements, including restrictive covenants and exclusivity arrangements, to hinder rival supermarkets from opening nearby.

The CMA's provisional view was that the three no longer qualify as limited assortment discounters and meet its criteria for large grocery retailers: stores larger than 1,000 square metres, a full grocery range and direct purchasing through integrated wholesaling. It cited the scale and geographic coverage of their stores and said various sources rank Aldi and Lidl among the top 5 retailers in a UK food and grocery market estimated at £215 billion.

No final decision had been made. The CMA invited views by 5pm on Monday 7 September 2026 and said it would consider responses before final decisions in the autumn. Juliette Enser, the CMA's Executive Director of Competition Enforcement and Markets, said the aim was to let shoppers choose where to spend their money.