Why most contractor rates are too low
Most contractors set their rate by looking at what others charge, then pitching slightly below to win work. The problem is that rate has no connection to your actual costs.
A sustainable contractor rate must cover every cost that makes your business run — not just the hours on site, but the hours between jobs, the insurance you pay quarterly, the fuel you use daily, the tools you replace, and the tax you owe at the end of the year.
When those costs are not built into the rate, every quote that looks profitable on paper is quietly losing money.
The average UK contractor underprices by 10–30% once real overhead and downtime are factored in. The gap is usually invisible until cash flow becomes a problem.
What a contractor rate must cover
- Direct job costs — materials, subcontractors, equipment hire, fuel to and from site
- Fixed overhead — insurance, professional subscriptions, accounting, vehicle costs, tools and equipment
- Downtime — days between jobs, admin days, holidays, sick days, training
- Tax liability — income tax, National Insurance, corporation tax if applicable
- Profit margin — the money that makes the business worth running
How to calculate your contractor rate — step by step
- List all annual business costs. Include every expense: insurance, tools, fuel, software, professional memberships, vehicle, and any other overhead. Do not guess — use your last 12 months of bank statements.
- Estimate billable days. Start with 365. Remove weekends (104), holidays (25), sick days (8), admin and travel days (15–20), and gaps between jobs (15–30). Most contractors bill between 180 and 220 days per year.
- Divide total costs by billable days. This is your break-even day rate — the minimum you must earn each working day before you make a single penny of profit.
- Add your desired profit margin. A 10–20% margin is typical. Add it on top of the break-even figure.
- Convert to an hourly rate if needed. Divide the day rate by your average billable hours per day (usually 6–8 hours).
How RateCheck uses your rate to check every quote
Once you know your sustainable rate, every fixed-price quote you send must be tested against it. RateCheck takes the client price you plan to quote, adds up the expected job costs, and tells you whether the effective rate you are earning on that job is above or below what you need to stay profitable.
It flags jobs that look viable at first glance but are actually loss-making once materials, overrun risk, and overhead are included.
The calculation happens before you send the quote — which is the only time it is useful. Once the client has agreed a price, it is too late to correct an underpriced job.
Common contractor rate mistakes
- Using a rate based on what you earned as an employee (which included employer pension, holiday pay and sick pay that you now fund yourself)
- Forgetting that 30–40% of invoice value goes to tax before you can spend it
- Not accounting for the weeks each year when no work comes in
- Setting the same rate for all job types regardless of material intensity
- Cutting the rate to win work without recalculating the break-even
Frequently asked questions
How do I calculate my contractor rate?
Add up all your annual business costs. Divide by your expected billable days per year. Add a profit margin. The result is your minimum daily rate. For an hourly rate, divide the day rate by your typical billable hours per day.
What costs should a contractor include in their rate?
Direct job costs (materials, fuel, subcontractors), fixed overhead (insurance, tools, software, vehicle), tax liability, downtime between jobs, holidays, and a profit margin. Most contractors forget downtime and tax, which are usually the largest hidden costs.
How many billable days does a contractor work per year?
Most UK sole traders and contractors bill between 180 and 220 days per year after accounting for weekends, bank holidays, personal holidays, sick days, admin time, and gaps between jobs. Planning for 200 days is a reasonable starting point.
Why is my current rate not sustainable?
Most contractor rates are copied from competitors rather than calculated from actual costs. If your rate does not cover tax, overhead, and realistic downtime, you are effectively working below minimum wage once those factors are included.
Can I use this for fixed-price quotes as well as day rates?
Yes. Once you know your minimum day rate, you can check any fixed-price quote by dividing the net profit from that job by the days it will take. If the effective daily rate is below your minimum, the quote is underpriced. RateCheck does this check automatically.
Test a real quote now
Enter a job, add the costs, and RateCheck tells you instantly whether the quote is profitable.
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