The turnover you want, worked back to the rate that gets you there.
Your day rate
£406
What most people work out instead
£216
The second one understates what you need by 1.88×. Quote it and you work the whole year to land short.
£406 is £56,000 across 138 billable days — 230 available, 60% of them paid for.
£216 is £56,000 ÷ 260 weekdays — no holiday, no illness, and every working day billed.
Utilisation is the number that decides this. Not the rate — the share of your available days anybody actually pays for. Around 60% is typical for anyone selling time, once pitching, invoicing, admin and the gaps between jobs are taken out. At 60%, a five-day week is three billable days, and a £350 day rate is roughly £48,000 of turnover rather than the £91,000 that 260 weekdays would suggest.
This is turnover, not take-home. Income tax, National Insurance and whatever you draw as an owner all come out of the figure above. Deliberately not calculated here: the answer depends on sole trader versus limited company, salary versus dividends, and whether you're taxed in Scotland — and a confident wrong number would be worse than none.
A day rate isn't always the right shape. It's honest when you're selling execution — a day of your hands is a day of your hands. It actively underprices you when what you're selling is judgement, because the value of a good decision has nothing to do with how long it took to make. If you've ever solved something in an hour and felt awkward invoicing for it, that's the symptom.