CIS refund companies: are they worth the fee?

First: what a refund company actually does

There's no special "CIS refund" form. A sole trader gets overpaid CIS back by filing a Self Assessment tax return. Refund firms collect your CIS statements and records of your costs, fill in the return, file it as your agent, and deal with HMRC if there are questions.

That's a real service, and it saves time. But HMRC works out your refund from the same figures whoever files the return. A firm can't make HMRC pay more than you're owed; it can only make sure the right costs are claimed.

You can do exactly the same yourself, for free. Our guide to claiming a CIS refund yourself shows how.

What some well-known firms charge

These are the fees published on each firm's own website when we checked on 21 October 2026. They're for a standard CIS tax return. Prices change, extra services cost more, and each firm's terms differ — always check the current price and terms yourself.

HandySums isn't paid by, or connected with, any of these firms, and inclusion in this table isn't a recommendation. We've listed firms that publish a clear price. Many other firms and accountants offer similar services.

What it means for your refund

The fee matters most when the refund is small.

Worked example

Chris is a CIS subcontractor whose return shows a refund of £1,500.

On a £500 refund, the same fees would take between about half and over two-thirds of it. On a £4,000 refund, it would be 7% to 9%.

Questions to ask before you sign up

1. What's the total price, including VAT? Some firms quote prices before VAT.
2. How is the fee collected? Some take it from your refund before passing the rest on; others invoice you. Find out what happens if the refund is smaller than expected — or if you end up owing tax.
3. Who does HMRC pay? Check whether the refund goes straight to your bank account or through the firm.
4. What's included? Is it one tax year? Are earlier years, amendments or HMRC enquiries extra?
5. What happens next year? Some services renew automatically. Check how to cancel.
6. Are they regulated or a member of a professional body? Anyone can call themselves a tax agent. Membership of a body such as ICAEW, ACCA, AAT or CIOT means they follow a code of conduct and have complaints procedures.

When paying someone can make sense

• You have several years of unfiled returns to catch up on.
• Your records are a mess and you want someone to sort them out.
• You have other income — rental property, a PAYE job, overseas income — or capital gains.
• You're facing an HMRC enquiry or penalties.
• You'd simply rather pay than spend the time. That's a fair choice, as long as you know the cost.

In these cases a qualified accountant, who can also help with payments on account, VAT and Making Tax Digital, may be better value than a refund-only service.

When doing it yourself is the better deal

• You're a sole trader with only CIS income.
• You have your monthly CIS statements and a record of your costs.
• Your refund is modest, so a fee would take a big share of it.

For most subbies in that position, it takes an evening, not a weekend. The online return does the tax calculation for you.

Watch out for scams

HMRC doesn't contact people out of the blue by text, email or phone to say they're due a refund, or ask for bank details that way. If you get a message like that, don't click links or reply. Sign in to your HMRC account directly, or report it to HMRC.

Some "refund" adverts are from genuine firms, but always check you're dealing with a real business with a UK address, clear prices and reviews from real customers before you hand over your UTR or Government Gateway details. Never give your HMRC login to anyone — an agent should be authorised through HMRC's own system instead.