Of course you can pay it into a bank account. If it is `crossed` (two lines drawn across) you can NOT get cash at a post office anyway. But irrespective of whether it is `crossed` or `open` you can pay it into your bank account.
NO factor30 - I regularly pay postal-orders into my bank account. The only thing changed is that now they are printed out for the exact amount (no more stamps stuck on)complete with electronic coding so now they are treated exactly the same as any other cheque.