2 week IT contract

[TheCyclingProgrammer]

I believe also you should be able to avoid IR35 considerations since you could bill this as a ONE TIME specific piece of work which doesn't put you into the same category as essentially doing the same work as the "permies" in the office. A decent Solicitor / Accountant is still your best bet though.

If OP isn't working through his own Ltd company then IR35 doesn't apply anyway.

[Jessica@WhiteFieldTax]

Even though what makes income "self-employed" or just "other income" isn't really anything to do with the amount earned, would you say there is any kind of de minimis amount that you could put into the "Other Income" box on a SA before it would attract HMRC's attention? I wouldn't have thought they'd be concerned with anything under the small earnings limit for class 2 NI anyway. In other words, if no class 2 NI would have been due anyway, the income has been declared and tax has been paid, I'm not sure why HMRC would be bothered.

In HMRC's own guide, they do mention that one of the types of income that could go into Box 16 is "freelance income". For a short, one-off job, that the OP is talking about, wouldn't that cover it?

Fair point; income well under the class II / IV threshold should be safe. The "freelance income" bit is probably someone in HMRC corporate communications not really understanding what freelance is; they've probably heard the word and thought it sounded clever (as you will gather, I don't hold them in high esteem) - seriously, I'm not dounting what you've quoted, but I think its incorrect on their part and misleading.