Nationwide is sending letters to millions of customers to confirm a free £50 payment will be landing in their bank accounts.

The UK bank is paying £50 to more than 12 million customers as a “thank you” following a Virgin Money buyout last year, which it says made it “an even stronger force in UK banking”. The takeover deal saw Nationwide become the country’s second largest provider of mortgages and savings accounts, with the buyout marking the biggest banking deal since the financial crisis.

When it bought Virgin Money, Nationwide paused the lender’s plans to close some of its branches as part of a promise not to leave any town or city without a Virgin Money branch until at least 2028.

The £2.9 billion takeover was led by chief executive Debbie Crosbie who said the benefits would go towards improvements for customers.

Now the bank has confirmed it will make a gesture of £600 million – called the “big Nationwide thank you” – in recognition of the role its members played in making the deal possible.

Nationwide has said it will write to members who will receive the £50 payment from today (March 11) to inform them how and when they will get the cash.

Payments will then be made to more than 12 million members who had a savings or current account, or mortgage, at the end of last September, from April 9 until May 14.

The bank added that members must also have made at least one payment into or from their current account or savings, or had a balance of at least £100 in their accounts. Additionally, they must still have their accounts or mortgage at the time the payment is made.

The £50 payment is separate to Nationwide’s ‘fairer share payments scheme’, which periodically returns some of its profits to members.

Debbie Crosbie, Nationwide chief executive, said: “Nationwide became even stronger when it bought Virgin Money and we are already improving services for its customers.

“The Big Nationwide Thank You recognises the role our members played in building the financial strength that made the deal possible.”