The average CIS tax refund is between £2,000 and £3,000 per year, but your actual amount depends on three things: how much you earned, how much CIS tax was deducted, and how much you spent on legitimate work expenses. Some construction workers get back over £5,000. Others get a few hundred pounds. The worked examples below show where different trades typically land.
The Simple Formula
Your CIS refund = CIS tax already deducted minus tax you actually owe
That's it. The bigger the gap between what's been taken and what you really owe, the bigger your refund.
Three things push that gap wider:
- The personal allowance — You don't pay tax on your first £12,570 of income
- Business expenses — Every legitimate expense reduces your taxable profit
- Working patterns — Gaps between jobs mean periods where CIS was deducted but your annual earnings are lower
Worked Examples by Trade
Example 1: General Labourer — £28,000 gross income
| Item | Amount |
|---|---|
| Gross CIS income | £28,000 |
| CIS deducted (20%) | £5,600 |
| Travel expenses (mileage) | £3,200 |
| Tools and PPE | £600 |
| Phone (business portion) | £300 |
| Public liability insurance | £400 |
| Total expenses | £4,500 |
| Taxable profit | £23,500 |
| Personal allowance | £12,570 |
| Tax due (20% on £10,930) | £2,186 |
| Class 4 NIC (6% on £10,930) | £655.80 |
| Total tax + NIC owed | £2,841.80 |
| CIS already deducted | £5,600 |
| YOUR REFUND | £2,758.20 |
This is typical for a labourer who travels to different sites. The combination of the personal allowance and travel expenses creates a substantial refund.
Example 2: Electrician — £48,000 gross income
| Item | Amount |
|---|---|
| Gross CIS income | £48,000 |
| CIS deducted (20%) | £9,600 |
| Travel and vehicle costs | £4,800 |
| Tools and test equipment | £1,500 |
| Training (18th Edition, inspection courses) | £800 |
| PPE and workwear | £400 |
| Insurance | £600 |
| Phone and admin | £500 |
| Total expenses | £8,600 |
| Taxable profit | £39,400 |
| Personal allowance | £12,570 |
| Tax due (20% on £26,830) | £5,366 |
| Class 4 NIC (6% on £26,830) | £1,609.80 |
| Total tax + NIC owed | £6,975.80 |
| CIS already deducted | £9,600 |
| YOUR REFUND | £2,624.20 |
Even on higher earnings, the refund is significant because of legitimate trade-specific expenses.
Example 3: Plumber — £36,000 gross income
| Item | Amount |
|---|---|
| Gross CIS income | £36,000 |
| CIS deducted (20%) | £7,200 |
| Van running costs (fuel, insurance, tax) | £3,800 |
| Tools and equipment | £1,200 |
| Materials (self-supplied) | £800 |
| PPE | £350 |
| Insurance | £500 |
| Training (Gas Safe renewal, courses) | £600 |
| Phone | £400 |
| Total expenses | £7,650 |
| Taxable profit | £28,350 |
| Personal allowance | £12,570 |
| Tax due (20% on £15,780) | £3,156 |
| Class 4 NIC (6% on £15,780) | £946.80 |
| Total tax + NIC owed | £4,102.80 |
| CIS already deducted | £7,200 |
| YOUR REFUND | £3,097.20 |
Plumbers often have higher vehicle costs and materials expenses, leading to a healthy refund.
Example 4: Bricklayer — £42,000 gross income
| Item | Amount |
|---|---|
| Gross CIS income | £42,000 |
| CIS deducted (20%) | £8,400 |
| Travel (mileage at 45p) | £4,050 |
| Tools (trowels, levels, mixing equipment) | £700 |
| PPE and workwear | £450 |
| Insurance | £500 |
| Phone | £350 |
| Subsistence (meals on site away from home) | £1,200 |
| Total expenses | £7,250 |
| Taxable profit | £34,750 |
| Personal allowance | £12,570 |
| Tax due (20% on £22,180) | £4,436 |
| Class 4 NIC (6% on £22,180) | £1,330.80 |
| Total tax + NIC owed | £5,766.80 |
| CIS already deducted | £8,400 |
| YOUR REFUND | £2,633.20 |
Example 5: Part-Year Worker — £18,000 gross income (6 months of work)
| Item | Amount |
|---|---|
| Gross CIS income | £18,000 |
| CIS deducted (20%) | £3,600 |
| Travel | £1,500 |
| Tools | £400 |
| PPE | £200 |
| Insurance | £500 |
| Total expenses | £2,600 |
| Taxable profit | £15,400 |
| Personal allowance | £12,570 |
| Tax due (20% on £2,830) | £566 |
| Class 4 NIC (6% on £2,830) | £169.80 |
| Total tax + NIC owed | £735.80 |
| CIS already deducted | £3,600 |
| YOUR REFUND | £2,864.20 |
Part-year workers often get the best refund-to-income ratio because the personal allowance covers a larger proportion of their earnings.
What Affects the Size of Your Refund?
Makes your refund BIGGER:
- Lower annual income (more of it falls within the personal allowance)
- More legitimate expenses (especially travel — this is usually the biggest one)
- Gaps between jobs during the tax year
- Working at multiple temporary sites (more travel to claim)
- Buying your own tools, PPE, and materials
Makes your refund SMALLER:
- Higher annual income (less proportional benefit from personal allowance)
- Fewer claimable expenses
- Working at one site for over 24 months (travel becomes non-claimable)
- Having other income sources (PAYE job, rental income)
Average Refunds by Trade
Based on typical incomes and expense patterns:
| Trade | Typical Annual Income | Estimated Refund Range |
|---|---|---|
| General Labourer | £24,000 – £32,000 | £2,100 – £3,100 |
| Bricklayer | £32,000 – £45,000 | £1,800 – £2,900 |
| Carpenter/Joiner | £30,000 – £42,000 | £1,900 – £2,900 |
| Electrician | £35,000 – £55,000 | £1,500 – £2,600 |
| Plumber | £32,000 – £50,000 | £1,800 – £3,100 |
| Plasterer | £28,000 – £40,000 | £2,000 – £3,000 |
| Painter/Decorator | £26,000 – £38,000 | £1,900 – £2,800 |
| Roofer | £30,000 – £45,000 | £1,800 – £2,800 |
| Groundworker | £28,000 – £40,000 | £2,100 – £3,100 |
These are estimates based on typical expense patterns. Your actual refund depends on your specific circumstances.
Get Your Exact Number
The examples above use simplified calculations. Your actual refund depends on your personal situation — your exact income, your specific expenses, whether you had any PAYE income, and other factors. If you're ready to start the process, follow our guide on how to claim your CIS tax refund.
Use our free CIS tax refund calculator to get a personalised estimate in under 60 seconds.
Frequently Asked Questions
How much is the average CIS tax refund?
The average CIS tax refund is between £2,000 and £3,000 per year. Some workers receive more, particularly if they have significant travel expenses or earned below the personal allowance threshold.
Can I get a CIS refund if I earned over £50,000?
Yes. Even higher earners can claim a refund if their CIS deductions exceed their actual tax liability after expenses. The refund may be smaller in proportion to income, but it can still be substantial.
Why do CIS workers overpay tax?
Because the 20% CIS deduction is applied to your gross pay without considering your personal allowance (£12,570 tax-free) or your business expenses. The flat 20% almost always takes more than you actually owe.
Do I get a refund if I didn't work the full year?
Often yes — and it can be a large one. If you only worked 6 months but CIS was deducted from all your earnings, a significant portion of those deductions will be refunded because your total income for the year is lower. Find out more about processing times in our guide to how long a CIS refund takes.
Related Guides
- How to Claim Your CIS Tax Refund — Step-by-step process for filing your return and getting your money back
- CIS Expenses You Can Claim — Complete list of allowable expenses that reduce your tax bill
- How Long Does a CIS Refund Take? — Processing times and how to speed up your refund
Last updated: November 2025. Examples use 2024/25 tax rates and thresholds. For exact figures, use our calculator or consult a tax professional.