IR35 and off-payroll working
We review each contract and your real working practices, then set out whether you sit inside or outside. Where a small client leaves the call to you, we document it properly.
IR35, VAT and a limited company that keeps more of every day-rate, run by an accountant who gets contract work.
You win work on your expertise, not on bookkeeping. As a specialist accountant for consultants and independent engineers, we take IR35, VAT and your limited company off your plate. Management consultant, contract civil or mechanical engineer, or a small consultancy with a team, the tax traps are the same, and a generalist usually misses them. Book a call with a consultant accountant who reads the contract before the tax return, on one fixed monthly fee.

Most accountants treat a consultant like any other small business. They file last year and move on, missing the things that actually move your tax bill.
A misjudged IR35 call. The Flat Rate Scheme left running when it has turned against you. A subscription or a site trip never claimed. So you overpay, and you never quite know where.
A specialist accountant for consultants works the other way round. We read the contract first, plan the year ahead, and we do not just record your numbers. We improve them.
We review each contract and your real working practices, then set out whether you sit inside or outside. Where a small client leaves the call to you, we document it properly.
We work out whether your own company or an umbrella keeps more in your pocket, and handle the setup, Companies House filings and year-end either way.
We track you against the £90,000 threshold and test the Flat Rate "limited cost trader" rule, so you are never stuck on a rate that quietly costs you money.
A tuned salary and dividend split with employer pension contributions, so you extract profit in the most efficient, compliant way each year.
Site mileage, professional indemnity insurance, List 3 subscriptions, home office, laptops and test kit, all claimed with the records to back them.
Company accounts, Corporation Tax and your Self Assessment filed on time. We tell you the bill months early, so nothing lands as a surprise.
IR35, the off-payroll rules, asks a simple question with an expensive answer. Strip away your company, and would HMRC see an employee? If yes, you are "inside" and taxed close to one. If no, you are "outside" and your limited company stands.
Since April 2021, when you work for a medium or large client, they decide your status and the agency or client deducts the tax. Work for a small company, though, and the call, and the liability, come straight back to your own company.
It turns on three things: control over how you work, whether you must do the work personally, and whether there is genuine mutuality of obligation. A "right of substitution" in name only does not save you.
We review your contract against how you actually work on the ground, flag the clauses that weaken your position, and document a defensible status. A wrong "outside" call can mean back-tax, National Insurance and penalties, so we get it settled before HMRC asks.
Two main ways to take on contract work. A limited company of your own, or an umbrella that employs you and runs everything through PAYE.
Outside IR35 on a decent day-rate, your own company usually wins. You take a small salary and dividends, claim a proper range of expenses, and keep more of each invoice. The trade-off is admin: company accounts, Corporation Tax and the filings that come with it.
Inside IR35, or on short or occasional contracts, an umbrella is often simpler and the tax difference shrinks. No company to run, but fewer expenses and a fee skimmed each week.
There is no single right answer, it depends on your rate, your IR35 position and how long you plan to contract. We will tell you which one puts more money in your pocket, and switch you over cleanly if that changes.
Through your own company, how you pay yourself matters as much as what you bill. The usual route is a modest salary topped up with dividends, but the right mix shifts each year as allowances and thresholds change.
A salary is a deductible cost for the company and protects your state pension record. Dividends are taxed more lightly than salary but only come from profit after Corporation Tax. Push too far on either and the benefit unwinds.
Employer pension contributions are the quiet winner. Paid by the company, they are a deductible cost, free of National Insurance, and a clean way to move profit into your own pension instead of HMRC.
We run the numbers on your salary and dividend split every year, keep one eye on your Self Assessment so the personal side stays in step, and make sure you are extracting profit the efficient way, not the default way.
More than most people claim. The trick is knowing what is genuinely "wholly and exclusively" for the work, and keeping the records to prove it.
On mileage you can claim the flat 55p a mile or actual running costs, and we pick whichever wins. Equipment usually qualifies for the Annual Investment Allowance, so the cost comes off your profit in full. We keep the bookkeeping behind it tidy, so a claim never falls over under scrutiny.
Most consultants register for VAT once turnover passes the £90,000 threshold, though many register voluntarily sooner because their clients are VAT-registered and reclaim it anyway.
The Flat Rate Scheme looks tempting: pay HMRC a single percentage of turnover instead of tracking every input. But there is a catch built for exactly your kind of business.
If you spend very little on physical goods, under 2% of turnover, or less than £1,000 a year, HMRC labels you a "limited cost trader" and forces you onto a punishing 16.5% rate. At that point the scheme almost always costs you more than standard VAT.
A consultant whose biggest costs are software, a laptop and their own time falls into this trap constantly. We test it every year, move you onto whichever scheme is cheaper, and keep you filing correctly under Making Tax Digital.
Pure design and consultancy by engineers sits outside the Construction Industry Scheme. Draw up the structure, sign off the calculations, advise from your desk, and CIS does not touch you.
But step into project management, site supervision or anything that looks like construction operations, and CIS can apply. That means 20% deducted at source if you are registered, or 30% if you are not, before the money reaches you.
We work out which side of that line your work falls on, register you correctly if it is needed, and reclaim any CIS over-deducted on your returns rather than leaving it sitting at HMRC.
Most independent consultants and contract engineers pay between £99 and £199 a month. Set against a single day-rate, it pays for itself.
No hourly rates. No surprise bills. One fixed fee, a named, qualified accountant who knows contract work, and a 30-day money-back guarantee.
Startups and small companies that need essential compliance and year-end support without VAT or payroll.
Growing businesses that need complete accounting services, VAT return management, and payroll handling.
Established businesses that want strategic mentoring, business planning, and a part-time finance director driving growth.
Yes. IR35 decides whether HMRC treats you as a disguised employee. For medium and large clients the client makes the determination, but if you contract with a small company the decision and the tax liability rest with your own company. We review your contracts and real working practices so you can take an 'outside IR35' position that would stand up to challenge.
Often not. Because consultants and engineers spend very little on goods, most fail the 'limited cost trader' test, under 2% of turnover, or under £1,000 a year, and are pushed to the 16.5% rate instead of 14.5% for professional services. At 16.5% the scheme usually costs more than standard VAT. We check it every year so you stay on the cheaper method.
Frequently, yes. If you're resolving genuine scientific or technological uncertainty, novel designs, bespoke systems, difficult materials or load cases, the work can qualify under the merged R&D expenditure credit scheme. Many accountants miss it because the engineering looks routine to them. We scope qualifying projects and prepare the technical and cost evidence HMRC requires.
It depends on what you actually do. Engineers acting in their normal professional discipline, design and consultancy, are excluded from CIS. But once you take on project management or are involved in executing and managing the construction work, CIS can apply, with 20% deducted at source (30% if you're not CIS-registered). We determine which applies and reclaim any over-deduction.
Yes, if the body is on HMRC's approved List 3, which includes the IMechE, IET, ICE and CIBSE. Where you hold more than one relevant membership, the relief stacks. We make sure these are claimed through your company or your return rather than overlooked.
If you use your own car, the HMRC simplified rate for 2026/27 is 55p per mile for the first 10,000 business miles in the tax year, then 25p per mile after that. Site visits, client meetings and travel to temporary workplaces all count. We keep the log straight so the claim is robust.
You get a named, qualified accountant on fixed monthly pricing, £99, £199 or £499 depending on your needs, with no long tie-in, just rolling monthly. We reply within 72 hours, work with Xero, QuickBooks, FreeAgent and Sage, and back it with a 30-day money-back guarantee.
Plain-English explainers, kept current with the latest HMRC rules.
Zmartly Ltd · 20–22 Wenlock Road, London N1 7GU · 020 8175 5145 · info@zmartly.co.uk
ICAEW, ACCA and AAT qualified accountants.