Getting this wrong is expensive. Your employment status for tax purposes is decided by looking at the whole picture, not a single clause, and backdated national insurance contributions can include employer-side costs if the engagement is reclassified. If HMRC decides your role was inside IR35 when it was treated as outside, you can be pursued for backdated income tax and national insurance contributions, plus interest and penalties, and it can affect how you pay tax on future contracts too.

IR35 is UK tax legislation that has applied since 2000, brought in to stop disguised employment, where someone works like an employee but pays tax through a personal service company. The rules have changed more than once since then, but the underlying question has stayed the same: are you genuinely running your own business, or working like an employee?

Since the 2021 reform, HMRC estimates around 120,000 workers have been affected by the shift in how private sector work is assessed, and it has raised billions in extra tax and national insurance along the way. That is not a small number, and it shows how easily contractors in every part of the contracting sector get caught out without a proper review.

Most of our clients come to us straight after being handed a status determination they don't understand. Many workers assume their paperwork alone protects them, but working practices matter just as much, and workers who move between assignments regularly benefit most from an ongoing review relationship. Contractors who ignore this can fall foul of rules that are stricter than they expect, especially now that different rules apply depending on the size of the end client you work for.

We keep clients updated by phone or email throughout the process. We start by reading your written contract in full, then ask you a set of questions about how the work actually runs and how you provide services to the end client. We ask exactly how you provide services to the client day to day, checking that against what the paperwork claims those services should look like. From there, we assess it against the tests HMRC and the tribunals actually use, including control, mutuality of obligation, substitution, financial risk, and how embedded you are within the client's own team.

If your status determination looks wrong, we can help you challenge it directly with the client. You get a detailed report setting out our view, with clear reasoning you can show to your client, your agency, or HMRC if it's ever needed. Every assessment we carry out is backed by a written explanation of our reasoning. These services cover contract wording, working practices, and the paperwork trail HMRC will want to see. We check our findings against HMRC's own CEST tool, but we don't rely on it alone.

Contractors who want to stay outside IR35 need more than a well-written contract; they need working practices that back it up. We also carry out contract reviews for renewals and extensions, not just new engagements, so your current contract stays covered even after your circumstances change. Workers engaged through their own limited company face different questions to those paid via umbrella arrangements, and we look at employment law tests as well as tax tests when we assess your position.

Prices for a professional IR35 contract review typically run from around £150 to £500 for a standalone review, though some accountants bundle it into a monthly package. These figures are a rough guide only, and the actual cost varies depending on your circumstances. Getting a second opinion on your IR35 status costs far less than an HMRC enquiry, and it gives workers the confidence to push back if a determination looks wrong.

Our contract reviews are written by people who read this legislation every week, not from a general checklist. We work with contractors UK-wide, reviewing contracts each year for workers engaged under off-payroll working rules by public sector bodies, small businesses, and large private sector clients. We support workers and businesses of every size, from sole contractors to teams supplying several clients, with services built around IR35. We've supported workers across IT, construction, healthcare and financial services, offering further support services beyond the review, some bundled into a monthly package. We deal with IR35 questions every week, not once in a while, on behalf of contractors and workers across every part of the off-payroll working rules. That keeps us close to how HMRC's approach actually plays out in practice, rather than relying on guidance alone.

Clients tell us the report is often more useful than the review itself, since it's something concrete to show HMRC or an agency's compliance team. Our reports are written to be used, not filed away. If a client, agency or HMRC ever asks how you reached your outside IR35 position, you'll have a clear, professional answer ready to show them. We also support contractors with the wider picture, comparing take-home earnings between limited company and umbrella contracting, advising on related services like accounts and Self Assessment, and reassessing your status whenever a contract is renewed. As an accountancy firm, we can also provide practical support around the wider financial considerations of contracting.