Sainsbury's is price matching Aldi - how much will you save? (PA) Sainsbury’s is cutting the prices of hundreds of products in a bid to match discount supermarket Aldi, who was named the UK's cheapest supermarket by Which?. The second largest supermarket in the UK aims to help customers “save more on their grocery shopping” with the new campaign. Chief Executive Simon Roberts announced a new initiative back in November, “to put food back at the heart of the business”. Roberts said: “We are making great progress in delivering our Food First plan and I’m determined that in these tough times, we do even more to help our customers save money.