Your first Self Assessment is a form asking what you earned, what it cost you to earn it, and what tax you have already paid — and for a private hire driver the honest answer to all three lives in records you either kept or did not. The return takes an evening when they exist. This walks a first-timer through the tax year, its deadlines, what the return asks, what to have ready, and driving alongside a PAYE job.
What is Self Assessment, and do you have to file one?
Self Assessment is HMRC’s system for people whose tax is not collected automatically, and a self-employed private hire driver is in it. Nothing is withheld from your payouts, so the return is how HMRC learns what you earned and works out what you owe. Filing is your responsibility, not the platform’s. There is a small trading allowance HMRC publishes below which casual income may not need reporting, but a licensed driver working shifts should assume it does not cover them.
Before you can file you need to have registered for Self Assessment and received a UTR, the ten-digit reference HMRC uses to identify you. The registration deadline falls in the October following the end of the tax year you started trading in, and the UTR arrives by post — so both are things to do early rather than in January. If you are unsure whether you need to file at all, HMRC publishes a checker, and five minutes there beats a year of wondering.
When does the UK tax year run, and when is the return due?
The UK tax year for individuals runs from 6 April to 5 April — not the calendar year, which catches almost every first-timer once. Everything earned and spent between those dates belongs on one return, and the boundary matters: a shift worked in early April and paid a week later needs a moment’s thought about which year it falls in.
The deadlines hang off the end of that year; confirm the current dates on HMRC’s site, because they are what penalties are calculated from. The gap between the year ending in April and the payment due the following January is the trap dressed as a gift: it looks like nine months of breathing room and functions as nine months of forgetting. Set money aside as it is earned, in an account you do not spend from, and January becomes an administrative event rather than a financial one.
- Tax year: 6 April to 5 April
- Register for Self Assessment: by the October following the end of the tax year you started in
- Paper return: the end of the following October
- Online return and the tax payment: the end of the following January
- Payments on account, if you owe them: the same January date and the following July
What does the return actually ask you for?
Your income, your allowable expenses, and your other income and tax already paid — and for a driver that means the self-employment pages, which for most people is the short version, SA103S. You enter turnover for the year, then allowable business expenses either as one total or split into HMRC’s categories, and the return works out the profit that tax and National Insurance are charged on.
Those pages also ask whether you use the cash basis or traditional accruals accounting — cash basis counting money when it moves, accruals counting it when earned or incurred. Cash basis is simpler and suits most drivers; whichever you pick, apply it to the April boundary the same way every year. Then comes everything that is not the driving: employment income and tax already deducted, savings interest, other income, and any reliefs you claim. The return is about you, not only about the business.
What should you have ready before you start?
Everything below, in front of you, before you open the form — because the failure mode of a first return is not difficulty, it is stopping halfway to go and look for something and never coming back. Gather first, type second.
If any of it is missing, get it now rather than at the form — platform statements especially, which are easiest to download while the account is live and the period recent.
- Your UTR and your Government Gateway login
- Your National Insurance number
- Every platform’s statements or annual summary for the tax year
- Your own record of earnings per platform, including tips
- Your mileage log for the year, if you are claiming the mileage allowance
- Receipts for business expenses — licensing, insurance, cleaning, equipment
- A P60 or P45 and any payslips, if you also had a PAYE job
- Details of other income: interest, dividends, property
What if you also have a PAYE job?
You file one return covering both, which is a very common position — days on the payroll, evenings and weekends on the apps. Employment income and the tax already deducted go on the employment pages from your P60; the driving goes on the self-employment pages. HMRC then looks at your total income for the year and works out the overall position.
Two consequences surprise first-timers. Your personal allowance is generally already used by the employment, so driving profit tends to be taxed from the first pound rather than after an allowance — which is why a driver who set aside nothing from app income can get an uncomfortable January. And National Insurance works differently for employment and self-employment and can be affected by what the payroll already collected, which is worth an accountant’s once-over in your first year. There is also a mechanism where a smaller balance can sometimes be collected through your PAYE tax code instead of as a lump sum, if you file early enough in the season.
What are payments on account, and why is the first bill sometimes bigger than expected?
Payments on account are advance instalments toward next year’s tax, and they are why a first bill can arrive larger than the tax you calculated for the year just gone. If your bill is above a threshold HMRC publishes, the system asks for the year you have filed plus an instalment toward the next one in January, and a second instalment the following July. Each instalment is based on a share of the previous year’s bill, and HMRC calculates it for you.
Nobody warns a first-timer, and it is the most common cause of a January panic. Plan for it from year one: set aside for the tax you know you owe and keep a buffer in case the instalment mechanism applies. If your income has genuinely fallen there is a process for reducing payments on account, but reducing them wrongly carries interest.
What do first-timers most often get wrong?
Filing a return built from bank deposits instead of records. Net payouts hide the fees withheld from them, say nothing about which platform the work came from, and contain no mileage at all — so a return built from deposits systematically overstates profit and understates deductions, meaning you overpay tax for the privilege of a harder evening.
The other classic errors are cheaper to avoid than to fix: registering late and collecting an avoidable penalty; claiming mileage with no contemporaneous log behind it; forgetting annual costs like licensing and insurance; losing access to platform statements before downloading them; and ignoring the April boundary so a week of earnings lands in the wrong year. Each is a record-keeping problem rather than a tax one, and the quarterly-planning article on this blog sets out the routine that prevents them.
BrewGig removes the first failure: earnings recorded per platform with tips and fees separate, expenses with receipts attached, automatic mileage capture on Pro and above, and a UK tax engine estimating the Self Assessment position against the real 6 April year and the SA103S pages. BrewGig is independent and not affiliated with, endorsed by or partnered with any platform named here; Bolt, FREENOW and all other platform names are the trademarks of their respective owners, and what each pays, charges or reports is defined by them — read your own statements, and take current rates, thresholds and deadlines from HMRC.