After nearly a year of phone calls to correct my address time and time again, 28 days of waiting till they'll acknowledge that they've not sent me the paperwork I need, but it's too late now so I'll have to start again, 6+ months of them threatening me with heavy fines if I don't fill in the paperwork that they admit they've not sent me because the computer system ate my US address AGAIN as the new system they had wouldn't accept non-UK postcodes(zipcodes) for a bit, requiring them to take the details again and again and again. Receiving mail with a fine in that had the last date I could complain against the amount 3 weeks before the postmark. Being told I can't sign up for the on-line version of the account as my postal address wasn't recognised being in the US (the WHOLE flippin point of online, it's to stop me popping round the office for a chat). Eventually receiving some paperwork (the wrong ones with me not actually living in the UK for 3 years now, but at least it was a start, or so I thought, next paperwork went missing and on further phone calls, they had the wrong address for me again somehow, even though the last stuff had somehow magically arrived on my doorstep).
After a years worth of this, holding up my US taxes to the point I couldn't wait anymore and had to file, gosh knows HOW many tons of paperwork they've sent to someone else (who's probably got all my social security/National Insurance details now), the HOURS of being on calls to get it sorted, I got my tax bill I owe the UK Government.
88pence.
They can go do rude things to themselves for it.