Sainsbury’s has reported an 8.1% increase in underlying pre-tax profit to £332m in its interim results, with customer numbers at an all-time high.

For the 28 weeks to October 2, total sales including Vat were up 7% to £11,944m, and total sales including VAT and excluding fuel were up 4.8%. Like-for-likes including VAT but excluding fuel were up 2%.

Chief executive Justin King said: “Customer numbers are now at an all time high of over 20 million transactions every week, which is up one million on last year, a clear indication of our growing universal customer appeal.”

In food, the grocer relaunched its £1bn Taste the Difference brand, while non-food is growing at three times the rate of food and its clothing brand Tu is now the tenth largest clothing retailer.

Sainsbury’s said its convenience business is now a £1bn business, and online growth is over 25% with Click & Collect installed at 140 stores. 540,000 sq ft of gross space was added in the period, and its first 100,000 sq ft store opened in Crayford.

King said: “As we enter the second half, we expect the economic environment to remain challenging. We remain confident that our universal customer appeal, combined with our strong space growth momentum, means we are in a good position to perform well in this environment.”

The grocer said sales of ethical products continues to grow, with Fairtrade showing sales growth of over 20%.

In the period, a further 1.4 million customers have signed up to Nectar, with now more than 12 million Nectar card holders.

It clothing brand Tu is now six years old and reached tenth place by volume. It has opened a sourcing office in Bangladesh in the period. Childrenswear, which is seventh in the market by volume, has been a “star performer” the grocer said, with its Back To School range “receiving praise for its high quality and excellent value”.

It said it is the fastest growing retailer of schoolwear and now fourth in the market, up from seventh last year.

In other non-food categories including books, and home textiles, it is achieving growth in excess of 20%.