As Post Office Card accounts can only be used to get cash at a Post Office I'd be wary if someone is offering this bank as a source of payment or even asking you to pay into it - only pensions and benefits can be paid in.
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The Post Office� card account is an ultra simple account that can only be used to receive benefit, state pensions and tax credit payments. No other payments, such as Housing Benefit, occupational pensions, or wages can be paid into it. You can only collect payments over the counter at a Post Office� branch. This account may suit you if you want a simple account that won't let you go overdrawn or incur any charges. No credit checks will be carried out when you open this account.
Cash withdrawal
A Post Office� card account will allow you to take cash out, free of charge, at any Post Office� branch using a plastic card and Personal Identification Number (PIN). Your card and PIN will also allow you to request a balance enquiry at any Post Office� branch.
Post Office� card account is offered by J. P. Morgan Europe Ltd through Post Office Ltd