The Eat Out to Help Out scheme increased restaurant spending by more than a third on Mondays, Tuesdays and Wednesdays, figures have revealed.
The government scheme – which gave diners up to 50% off their bill to a maximum of £10 each – finished on 31 August.
The discount for food and non-alcoholic drinks was introduced by Chancellor Rishi Sunak to help boost the struggling hospitality industry in the wake of the COVID-19 pandemic.
Popular restaurants – including Nando’s, Wagamama and Gourmet Burger Kitchen – were among tens of thousands of outlets to sign up.
Barclaycard Payments, which manages around 40% of UK transactions, said diners spent 34.2% more at restaurants during the subsidised days than on the same days before the scheme in July.
Research showed that Wednesdays were the most popular day, with spending increasing by 39.7%.
It found that almost four in 10 British people made use of the scheme – with 52% choosing to specifically eat out on the discounted days.
In total, 87,000 claims were made by businesses signed up to the government initiative, the Treasury has said. £336m had been claimed for 64 million diners for the week of 23 August, according to HMRC data.
However, despite the success of the scheme, the bank reported that the average transaction value on Mondays to Wednesdays remained somewhat stable.
Food costs rose from £11.85 in July to £11.91 in August.
Barclays said this indicates that the government subsidy encouraged diners to order more items than usual, in order to spend “roughly the same amount overall”.
Rob Cameron, chief executive of Barclaycard Payments, said the Eat Out to Help Out scheme had a “positive impact” for businesses in August.
“Restaurants across the UK will be looking to maintain this boost in trade, especially with the Christmas period now in sight”, he said.
The data found that almost one in five people plan on continuing to eat out more often to support the industry – with 18% saying they will return to restaurants they would not have otherwise visited without the government discount.
Many restaurants – including Pizza Hut, Bill’s and Pizza Pilgrims – have decided to continue offering 50% off most items without government support.