The Lemon Fool

X is employed part-time with gross pay of say £8000 p.a. and also runs a small one-person business with a turnover of less than £1000 p.a. Must X register for self-assessment given that self-employment income is under the £1000 trading allowance even though X’s total income is larger.
HMRC’s guidance notes imply that if X’s other income were over £2500 X must register even if self-employment income were £1!
Is this correct pls or am I misreading?

Excellent, ap8889 - many thanks. I looked but never found this one.
The only vagueness is in HMRC's question: Did you earn more than £1,000 from working for yourself?
DAK whether earn means income from customers or net profit when expenses have been deducted?

Because later on it says: What was your total income for the year? To work this out, add up all your income - for example, salary before tax, taxable benefits (such as a company car), and income from investments or pensions. Then take off anything you can claim tax relief on.

And finally (for the situation I originally posted) the systems says:
You do not need to send a Self Assessment tax return but You can still choose to send a return to claim tax relief on work-related expenses above £2,500

At which point my brain goes numb trying to work out whether startup expenses of say £1500 can be allowed against tax...