I can't add an awful lot except that I just registered over the phone and when I filled in my first tax return and had also be employed for part of that year, it calculated the tax paid already automatically so it is probably best for you to see an accountant to get everything completely straight before you have to do this as it sounds like you may get checked.
If you do it online, you have until end of Jan 2013 to submit your tax return for the tax year just ended (I always put it off until the last minute!!!) so you have plenty of time to get your figures straight, but notify HMRC asap.
Abbie
|