For UK sole traders
Most sole traders pay tax on money they didn't have to.
Windfall tracks your expenses at the point of purchase. It classifies each one against HMRC guidance, shows its reasoning, and gives you a year-end record you can stand behind.
No credit card required · Free for 30 days
Why this keeps happening
The problem has a name. Actually, it has three.
The Annual Reckoning Trap
Most sole traders structure their expenses around the year-end deadline. But memory for context degrades within hours of a purchase, not months. By the time you sit down to sort everything out, the information you need to make confident decisions is already gone.
The Grey Zone Tax
HMRC's guidance on allowable expenses isn't written for someone making a decision at a till. It's written in categories, with caveats, for people who already understand the framework. Most contractors either avoid ambiguous expenses entirely or guess, and worry they've guessed wrong. Both approaches are expensive.
The Point-of-Purchase Principle
Windfall is designed around a different moment. Photograph the receipt when it happens. The AI reads it, classifies it against HMRC guidance for your work type, explains the reasoning, and asks for your confirmation. The decision is made once, accurately, while the context is live.
Three steps
1. At the till. 2. In the app. 3. At year end.
Photograph the receipt the moment it happens
Open Windfall, photograph the receipt. The AI reads the vendor, amount, and date in seconds. No manual entry.
Windfall classifies it and shows its reasoning
Every expense is classified against HMRC's allowable expense framework for your work type. The reasoning is shown in plain language — you see why something is claimable, not just that it is. You confirm or adjust.
Finish the year with a record you can stand behind
At year end, export a complete, categorised record — every expense organised by category, ready to file. No reconstruction. No gaps. No hoping you remembered everything.
You're probably missing these
HMRC allows all of these for sole traders. Most people claim fewer than half.
Windfall knows the eligibility rules for each of these and applies them to your specific circumstances. - we ask you for your profession.
It pays for itself quickly.
At the 20% basic rate, a single missed home office month can be worth more than the cost of a full year's subscription. The average sole trader who uses Windfall consistently finds enough unclaimed deductions in the first quarter to cover the annual fee several times over. If you're a higher-rate taxpayer, your actual saving will be greater.
Less than the cost of one missed deduction
Built by a sole trader, for sole traders
I spent 28 years in digital design - with many of those years as a contractor. I knew how to build systems for real human behaviour. What I hadn't planned for was spending years applying none of that to my own expenses — tracking what I could in a spreadsheet, and arriving at every year end knowing I'd probably missed things.
Windfall is the tool I needed from day one of contracting. Built around the moment that actually matters, not the deadline that's already too late.
Mark Wu, founder
Simple, honest pricing
Full access to every feature. No credit card required.
- Receipt capture
- AI categorisation
- HMRC reasoning shown
- Accountant export
- MTD quarterly summaries
Everything you need as a sole trader, for less than the cost of one missed deduction.
- Receipt capture
- AI categorisation
- HMRC reasoning shown
- Accountant export
- MTD quarterly summaries
- Priority support
Full access, billed monthly. Cancel any time.
- Receipt capture
- AI categorisation
- HMRC reasoning shown
- Accountant export
- MTD quarterly summaries
£59/year works out at £1.13 a week. At 20% tax, one claimed £300 expense saves £60 — the subscription paid for itself. At 40%, you need half that.
Still thinking about it?
There's no sale coming. No discount code. If the problem is real — and you know whether it is — 30 days costs nothing to find out.
No credit card required