Sally's Journal

HMRC allow you to declare casual or freelance income without treating it as a full self-employed business. There are boxes on the tax return form to declare the total such income, allowable expenses, and any tax already paid there (as well as wanting a description of how you earned it).

That's interesting. When this happened to me a few years ago I found various boxes on the tax return that looked possibly like what you're describing here, but none of them seemed to be clearly applicable based on the detailed wording, so I gave up and phoned HMRC's helpline. I described the facts of the case and asked how I should translate them into tax-return-boxes, and they told me I should do a full-on self-employment page, so I did that (and – possibly as a result? – paid NI as well as income tax on the money).

Perhaps they told me that because the money in question was a little more than we're discussing here. (I can't remember whether I actually told them how much it was when I rang the helpline. If I didn't, then perhaps they told me that because it was the safe option if the amount was uncertain...) But if there is a box I could have used legally with less hassle, then I'm faintly annoyed that I didn't manage to find that out and do it!