Why I built this
Building websites for UK tradespeople puts you in a unique position. You spend a lot of time talking to sole traders about their businesses: what they do, who their customers are, and what they want to earn. And one thing comes up constantly: pricing.
Not a lack of skill or ambition, but a genuine uncertainty about what to charge. I've spoken to qualified plumbers undercharging by £15 an hour because they were guessing. Electricians quoting jobs without factoring in their van costs or the tax they'd owe. Builders hitting their income target on paper but still struggling because they hadn't accounted for the 8 weeks a year they don't bill anything.
Most of the tools available online either oversimplify the problem (just divide your salary target by 52 weeks) or are buried inside paid software that requires a subscription. So I built WhatToCharge.co.uk: free, no sign-up required, and built around how sole-trader tradespeople actually work.
What makes the calculators different
Most day rate calculators ask "what salary do you want?" and divide by 260 working days. That's wrong in at least three ways: it ignores overhead costs entirely, it doesn't account for non-billable time, and it confuses gross revenue with take-home pay. A tradesperson using those calculators will set a rate that doesn't cover their actual costs.
The WhatToCharge calculators account for:
- Real overhead costs: van finance or lease, insurance, tools and equipment, professional memberships, accountant fees, phone and marketing
- Non-billable time: holidays, sick days, training days, admin, travel between jobs, and unpaid quoting visits
- UK tax and National Insurance: using HMRC's actual income tax bands and Class 4 NI rates for 2025/26, so the result is real take-home pay, not gross income
- Profit margin: the difference between breaking even and building a sustainable business with a financial cushion
Every calculator is pre-filled with realistic defaults for each trade, updated each April at the start of the new tax year.
The rate data
The trade rate pages on WhatToCharge draw on a mix of publicly available industry data, job advertising rates, and direct conversations with tradespeople across the UK. Figures are reviewed and updated regularly. The pages are not set-and-forget.
UK trade rates vary significantly by region. A plumber in central London charges materially more than a plumber in North Yorkshire, for legitimate reasons: van costs, parking, congestion charges, and local cost of living all contribute. Where possible, pages include regional breakdowns rather than a single national average that misrepresents most of the country.
How the site is funded
WhatToCharge.co.uk earns revenue through display advertising (Google AdSense) and occasional affiliate links to relevant products like trade insurance and accounting software. These are disclosed where present. There are no sponsored "recommendations," no paid placement in trade rate figures, and no subscription products. The calculators are and will remain free.
Questions or feedback? If you spot a rate that looks wrong, a calculator that doesn't behave as expected, or have a suggestion for a trade or tool we haven't covered, feel free to reach out via stellarcoredesigns.com.
Accuracy & disclaimer
Tax rates used in the calculators are based on the current 2025/26 HMRC figures and are updated each April. Trade rate data is indicative based on industry averages. Individual rates will vary based on experience, location, qualifications, and the specific nature of the work. While every effort is made to keep all figures accurate and current, the tools on this site are for informational and guidance purposes only and do not constitute financial or tax advice. Always consult a qualified accountant for advice specific to your situation.