There is no standard amount. The size of yours is decided by how much was deducted, what you spent to do the work, and whether any of your income was already taxed elsewhere. Here is how to get to a rough figure from your own paperwork.
Why we do not publish an average
Refund companies publish the average from their own client book. Those numbers are real, but they describe the mix of people who came to that company — and a business whose turnover is mostly materials will be nowhere near the same figure as a labour-only groundworker on the higher rate. We have not measured ours, so we are not going to quote one.
What follows is the arithmetic instead. You can do it on the back of an envelope with your deduction statements in front of you.
A labour-only subcontractor invoices £48,000 in the year, all inside CIS, all at the 20% rate with no materials. £9,600 is deducted at source and £38,400 is received.
Costs for the year come to £9,000 — van running costs, tools, protective equipment, phone, insurance and accountancy. Taxable profit is therefore £39,000.
The tax and Class 4 National Insurance due on £39,000 is worked out in the return, after the personal allowance. Whatever that figure comes to, £9,600 has already been paid towards it. The refund is the difference.
Two things move that number a long way: being on 30% instead of 20% for part of the year, and having costs you did not claim because you had no record of them.
The rate you were on. On the same £48,000, the higher rate takes £14,400 instead of £9,600. Nothing about the tax you owe has changed, so the extra £4,800 comes back in full. If you have been on 30% for a whole year it is worth finding out why before the next one starts.
Whether materials came out of the base. Materials you directly incurred should reduce the payment the deduction is charged on. Where the contractor buys the materials and recharges them to you, you have not directly incurred the cost and no reduction is due — so the same job produces a very different deduction depending on who bought the materials. The deduction calculator shows the effect.
Whether you had a job as well. Employment income in the same tax year uses the personal allowance first, so there is less of it left to shelter the self-employed profit, and the refund is smaller.
Part-year working. Someone who worked six months and then stopped has had deductions taken on a run rate that assumed a full year of income. Those are often the largest refunds of all, and the least often claimed.
Every one of these is a reason the deduction was wrong for you. The tax itself was right. If the refund is large and repeats every year, the deduction is the thing to fix. See gross payment status.
Different firms publish different averages, because each one is describing its own client book rather than the industry. We have not measured ours and will not quote somebody else's. The size of any individual refund is set by how much was deducted, which follows from turnover and whether you were on the 20% or 30% rate; by how much of that turnover was labour rather than materials; by the costs you can evidence; and by whether other income in the same tax year used up your personal allowance.
Not necessarily, and often the opposite. More turnover means more deducted, but it also means more tax owed, and the personal allowance is a fixed amount that does not grow. The refund is the gap between what was deducted and what was owed, so it is widest for someone on the higher rate, or with a lot of allowable costs, or who worked only part of the year.
Yes, and it will usually be the whole of what was deducted, because there is no tax to set it against. A trading loss can also be relieved against other income in the same year or carried back, which can produce a repayment of tax paid elsewhere. Losses are worth taking advice on rather than simply carrying forward by default.
No. It is your own money being returned because too much was taken. It is not income and it does not go on the following year's return as income.
Three months is enough to see the pattern and a full year is enough to put a number on it. We will tell you what is likely to come back and whether the deductions were right in the first place.