A five-year agreement with dozens of banks will deliver a welcome boost to the state-owned company's finances.
The Post Office will next week unveil a £1.75bn deal with dozens of banks which will allow their customers to continue using Britain’s biggest retail network.
Sky News has learnt the next Post Office banking framework will be launched next Wednesday, with an agreement that will deliver an additional £500m to the government-owned company.
Banking industry sources said on Friday the deal would be worth roughly £350m annually to the Post Office - an uplift from the existing £250m-a-year deal, which expires at the end of the year.
The sources added that in return for the additional payments, the Post Office would make a range of commitments to improving the service it provides to banks' customers who use its branches.
Banks which participate in the arrangements include Barclays, HSBC, Lloyds Banking Group, NatWest Group and Santander UK.
Under the Banking Framework Agreement, the 30 banks and mutuals' customers can access the Post Office's 11,500 branches for a range of services, including depositing and withdrawing cash.
The service is particularly valuable to those who still rely on physical cash after a decade in which well over 6,000 bank branches have been closed across Britain.
In 2023, more than £10bn worth of cash was withdrawn over the counter and £29bn in cash was deposited over the counter, the Post Office said last year.
A new, longer-term deal with the banks comes at a critical time for the Post Office, which is trying to secure government funding to bolster the pay of thousands of sub-postmasters.
Reliant on an annual government subsidy, the reputation of the network's previous management team was left in tatters by the Horizon IT scandal and the wrongful conviction of hundreds of sub-postmasters.
A Post Office spokesperson declined to comment ahead of next week's announcement.