SheScribbles, you don't need to get an accountant. Self-employed stuff is actually very straightforward, though as always with writers, the forms don't always seem to fit our situations terribly well, and the tax office helplines are apparently genuinely helpful, as well as the Society of Authors (sub. tax-deductible).

Personally I'm a wimp, and do use one - £400 or so well spent (and you don't have to pay tax on that fee, of course, just as with your agent's commission) not least when the Inland Revenue send me a thing saying I owe more tax than I paid back in January, (which I don't) and all I have to do is post it to my accountant and let him talk to them... I know he's saved me more than his fee most years, in knowing what I can claim as an expense, and all about specialist stuff like 'averaging' that tries to even out the lumpy nature of writing income - even if the sums involved aren't huge, it can still save you something like a third of the tax.

Emma

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I'm sure Naomi's right - it's whether your main job is employed that matters. Loads of people have bits of self-employment and the Revenue understand that. But generally speaking, it's more tax efficient to be self-employed, so make the most of what you can, and just thank your lucky stars if the deal doesn't mean you have to be VAT-registered, which is much, much, much worse, by all accounts...

Emma

If you're employed and you earn money from something like writing you have to register as self-employed. Then when you fill out a tax return you put the details from your P45/P60 on the return. You don't need to tell your employer you're self-employed though. Although I haven't made any money from writing I'm in that position as a web developer in employed and self-employed capacities.

An accountant knows the system so as long as you've earned a bit of money they will save you more in tax than it would cost to pay them. Having said that if you decide to go it alone the forms are pretty easy to do and despite what you think the IR are actually very helpful. I'm terrible with paperwork and I even I manage to do my own tax return!