For most sole traders, mileage is a line on the tax return. For an owner-driver courier, mileage is the entire business model. You are paid to move, your biggest cost is moving, and your biggest tax deduction is a number that only exists if you recorded it. Sloppy courier mileage tracking does not lose you a few quid; at your annual mileage it can lose you thousands, and a weak logbook is exactly the kind of thing HMRC asks about.
The AMAP maths at courier volume
If you use HMRC's simplified mileage method, the approved rates for cars and vans are 45p per mile for the first 10,000 business miles in a tax year and 25p per mile after that. At normal-person mileage those are small numbers. At courier mileage they are not:
- 10,000 miles: £4,500 of deductions.
- 30,000 miles: £4,500 plus 20,000 at 25p, so £9,500.
- 45,000 miles: £4,500 plus 35,000 at 25p, so £13,250.
Those figures come off your taxable profit, so the tax saved depends on your band, but the point stands at any rate: the difference between an evidenced 42,000 miles and a shrugged I-guess-about-35,000 is real money, every single year. Rules have conditions and your situation is your own, so run the method choice past an accountant, but do not let the record-keeping be the reason you claim less than you drove.
Mileage rate or actual costs: keep the receipts either way
The simplified mileage rate is designed to cover the running of the vehicle: fuel, servicing, insurance, wear. That means you cannot claim the 45p rate and separately claim fuel and repairs for the same van. So why photograph every fuel and maintenance receipt? Two reasons. First, until your accountant runs the numbers, you do not know which method leaves you better off, and at heavy mileage with an expensive van the actual-costs method sometimes wins; no receipts, no choice. Second, receipts corroborate your mileage log: a fuel pattern that matches your claimed miles is exactly the sort of consistency that makes an enquiry short. Our general guide to mileage tracking for UK tradespeople covers the record-keeping basics; couriers just need all of it, at ten times the volume.
What an HMRC-proof mileage record looks like
There is no prescribed form, but a log that survives scrutiny answers four questions for every business journey: the date, where you went from and to, why (the business purpose), and how many miles. For self-assessment you should keep your records for at least five years after the 31 January submission deadline of the relevant tax year. A multi-drop day does not need sixty entries; a sensible summary works: date, depot to round to home, parcel delivery round for the contractor, 187 miles. What does not work is reconstructing a year from memory the week before the deadline. The log has to be contemporaneous, or close to it, to be worth anything.
Multi-drop days: recording without stopping
The practical problem is that couriers have no admin time built into the day. You are against a manifest and a cut-off; nobody is opening a spreadsheet at a red light, and nobody should be. The habit that actually sticks is the end-of-shift message: the moment the van is parked, before you go inside, send yourself the day in one line. Odometer start and end, the round, anything unusual. Twenty seconds, done in the cab, every day. A record made daily by message, with a timestamp you did not fake, is a far stronger document than a beautiful spreadsheet typed up in January.
Invoicing the contractor weekly, without slippage
Most owner-drivers invoice a contractor or two on a weekly cycle, and the failure mode is slippage: the invoice goes in two days late, payment terms start two days late, and your cash flow inherits the delay forever. Worse is the disputed week, when the contractor's system says you worked four days and you know it was five. Your own daily log is your defence; their portal is theirs. Treat Friday invoicing like a delivery with a cut-off time: same day, every week, from your own records, with the week's mileage and any deductions checked against your log before you press send.
Where GraftG comes in
This end-of-shift-by-message habit is exactly what GraftG is built around, and it is coming soon. GraftG turns WhatsApp into your back office: text your miles to one number and they are logged with a timestamp; photograph the fuel or service receipt at the counter and it is filed; send the week's details and the contractor invoice goes out; the job tracker keeps each round and each week straight. No app to download, no dashboard, nothing to learn, because you already use WhatsApp between drops. For a trade where the whole tax position rests on a logbook, a record you build by message every day is the strongest one you can have.
GraftG launches soon. If your mileage log is currently a guess, join the early access list at graftg.co.uk and be ready for it. Your admin sorted. Just WhatsApp it.