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# Getting and Working with an Accountant
You can file your own tax return. Plenty of subbies do. But once you're doing more than about £30k turnover or you're CIS and want your refund sorted properly, a decent accountant is usually worth the money. This guide covers when you need one, what they should cost, and how to spot the ones you should avoid.
Rule of thumb: a good accountant pays for themselves. If they can't save you more than their fee, you either don't need one or you've picked the wrong one.
When Do You Actually Need One?
You probably don't need an accountant if:
- Your income is straightforward (one contractor, few expenses)
- You're comfortable using HMRC's online tools
- Your turnover is under £30k and you keep decent records
You probably do need one if:
- You're CIS and want to make sure your refund is right
- You're VAT registered or approaching the threshold (£90,000 in 2025-26)
- You have multiple income streams (subbing for different contractors, side jobs, rental income)
- You're thinking about going limited
- You hate paperwork and you know you'll leave it until 30 January
Most tradespeople fall somewhere in the middle. The question isn't whether you can do it yourself. It's whether your time is better spent on tools than on tax returns.
What Should an Accountant Cost?
Typical prices for sole trader construction workers (2025-26 rates):
| Service | Cost |
|---|---|
| Basic Self-Assessment filing only | £150-£400/year |
| Bookkeeping + SA filing | £50-£150/month |
| Limited company accounts + SA + payroll | £100-£250/month |
| Ad-hoc CIS refund only | £100-£300 (one-off) |
Prices vary by area. London and the South East are pricier. Online-only accountants are often cheaper but you lose the face-to-face.
Don't shop on price alone. The cheapest accountant who misses £2,000 in allowable expenses has cost you £400 in tax you didn't need to pay.
The CIS Angle
If you're on CIS, a good accountant is almost always worth it.
Here's why. Your contractors deduct 20% (or 30% if you're unverified) from every payment. That money goes to HMRC against your tax bill. If you've got decent expenses, you're probably owed a refund.
Example: A subbie earns £40,000 gross with £8,000 in allowable expenses. CIS deductions at 20% = £8,000 already paid to HMRC. Actual tax due on £32,000 profit is roughly £3,900. That's a refund of over £4,000.
A good accountant finds you £2,000 more in expenses you didn't know you could claim. That's another £400 back in your pocket. Their fee of £200-£300 is covered and then some.
Tip for new starters: keep every CIS statement (CIS301) you get from contractors. Your accountant needs these to prove what's already been deducted. If you lose them, the refund process gets much harder.
What They Need From You
Make their life easy and they'll do a better job for less. Give them:
- Receipts for everything. Tools, materials, van fuel, PPE, phone bills, insurance. Paper or digital, just keep them.
- CIS statements (CIS301s). Every single one from every contractor.
- Mileage log. If you use your own vehicle. Date, from, to, miles, reason.
- Van costs. If the van is in the business: fuel, servicing, insurance, finance payments.
- Tool purchases. Power tools, hand tools, specialist kit.
- Bank statements. Business account, ideally separate from personal.
- Any other income. Rental, PAYE from a side job, interest.
The more organised you are, the less time they spend sorting your mess out, and the lower your bill.
Finding One
ACCA (Association of Chartered Certified Accountants)
Search at accaglobal.com/findaccountant. Filter by location and specialism.
ICAEW (Institute of Chartered Accountants in England and Wales)
Search at icaew.com/find-a-chartered-accountant.
Word of mouth
Ask other subbies who they use. If three brickies on the same site all use the same accountant, there's probably a reason.
Online accountants
TaxScouts, Crunch, FreeAgent. Cheaper, app-based, good for straightforward returns. Less useful for complex CIS situations or if you want someone to actually talk to.
Tip for new starters: book a free initial consultation with 2-3 accountants before choosing. Most offer one. Ask what they know about CIS. If they look blank, move on.
Red Flags
Walk away from any accountant who:
- Guarantees a specific CIS refund before seeing your records. Nobody can promise that. Your refund depends on your numbers.
- Doesn't ask about your CIS status. If they don't know what CIS is, they don't know construction.
- Won't give you a fixed fee upfront. "It depends" is fine at the first meeting. "It depends" at the point of signing up is not.
- Is impossible to reach between January and March. If they ghost you during the busy season, they're overloaded.
- Suggests anything that sounds too clever. Aggressive tax avoidance schemes have a way of coming back to bite you. If HMRC investigates, it's your problem, not your accountant's.
What a Good Accountant Does Beyond Your Tax Return
- Tells you when to register for VAT (and which scheme suits you)
- Advises on going limited vs staying sole trader
- Chases HMRC on your behalf if there are delays
- Flags when Payments on Account are coming so you're not surprised
- Keeps you compliant so you never get a penalty letter
Sources
- ACCA, "Find an accountant directory"
- ICAEW, "Find a chartered accountant directory"
- HMRC, "Construction Industry Scheme guidance," 2025
- gov.uk, "Self-Assessment tax returns"
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