Contractors IR35

How to appeal an SDS decision on your IR35 status

In Kingsbridge’s recent contractor survey, an enormous 90% of contractors that had appealed an IR35 status, told us that they…

Kingsbridge by Kingsbridge
Two people discuss a contract

In Kingsbridge’s recent contractor survey, an enormous 90% of contractors that had appealed an IR35 status, told us that they did not find the IR35 appeals process easy and that they did not receive a fair hearing. 13% of contractors had appealed a Status Determination Statement (SDS) provided by their end client.

Your SDS will tell you if your end client believes you to be ‘inside’ or ‘outside’ IR35. This is based – or should be based – on a review of your contract and working practices to determine if you are to be considered genuinely self-employed for this particular engagement (outside IR35) or if you should be treated as an effective employee in terms of taxation (inside IR35).

Bear in mind that each SDS is based on the terms of each engagement you have. So at any one time, you could be working multiple contracts for multiple clients and have different statuses for each of them. But what happens if you’re not happy with the conclusion of your SDS? Kingsbridge has all of the facts for you.

Can I appeal an SDS?

The short answer is yes, you can appeal an SDS if you don’t agree with it. Whoever produces your SDS (this would usually be your end client) is required by HMRC to have an appeal process in place. The rules set out by HMRC means that your client has to respond within 45 days of receiving your appeal, although it does not mean that they have to agree with you. It’s also worth noting that your original determination will stand during this period.

To appeal a determination, you should contact your client with the details that you disagree with and put forward your arguments as to why you believe the determination should be different. Be sure to highlight everything in your contract and working practices that supports your stance, including personal service/right to substitution, mutuality of obligation (MOO) and control.

Make sure you keep a record of all correspondence to refer back to and should your case ever be investigated by HMRC.

Should I go straight to an appeal if I’m not happy with my IR35 status?

The soft-landing put in place by HMRC for the first year of the IR35 reforms has now ended  which means HMRC will come down a lot harder on those that don’t comply with the IR35 legislation. This includes not taking due care when determining a contractor’s status. If you’re not happy with your SDS it’s worth, then, simply flagging this with your client or recruiter.

The person responsible may give you a good reason why they gave the determination they did or, if they know they didn’t really give due care, they may go back to the drawing board. However, if you’re still not happy then you should submit an appeal using the process we outlined above.

What happens when I submit an IR35 status appeal?

Once you’ve submitted your appeal, as mentioned, your client has 45 days to respond. There are, ultimately, just two potential outcomes. If your client agrees with your appeal, you should be issued with a new SDS with your new determination and the reasons for it. If your client doesn’t issue this, be sure to push for it as you will need it for your records.

If your client disagrees with your appeal, they should let you know along with the reasons why they are upholding their decision. If they don’t give reasons, make sure you ask for them. If you’re not happy with their decision, you can choose to terminate the contract or continue working as inside IR35 and be taxed accordingly.

Bear in mind, this won’t affect other determinations with other clients.

What help can I get in determining my IR35 status?

If you are unhappy with your SDS and want to appeal, it’s definitely worth seeking independent advice to corroborate what you believe or, indeed, to confirm to you that the determination is correct. One way of getting such advice is to use a status determination tool.

While tools such as HMRC’s Check Employment Status for Tax (CEST) exist, contractors don’t generally find them to be reliable. An option that can give you more confidence in your determination is the Kingsbridge IR35 Status Tool.

This hybrid tool asks between 29 and 35 carefully crafted questions (which have been developed by Kingsbridge’s Head of Tax, IR35 specialist Andy Vessey) to get a rounded view of your contract and working practices. It will then generate an instant, accurate inside or outside IR35 status determination, along with a full report outlining the reasons for this status and the strengths and weaknesses of your case, ready for you to share with your end client.

If, however, your case is borderline, your answers are passed to one of our in-house IR35 experts for a manual review. After reviewing your case (and possibly asking you some further questions) they will issue your status and report. We believe that this hybrid approach is the best way to give you a quick, yet conclusive, result – all for just £50 plus VAT.

To find out more and get started, click here.

Related topics

Contractors IR35

You might also like...

Back to resources
Close up photo of female worker at a desk with laptop and calculator, representing article on what insurance contractors need
Contractor Guides Contractors 03 Nov 2026

What insurance contractors need?

We know it can be a minefield for contractors when it comes to purchasing the right contractor insurance to protect…

Image of a handheld drill on a work bench, representing guide on how to insure work tools for tradespeople
Trades Trades Life 09 Sep 2026

How to insure your tools: a tradesperson’s guide

Most tradespeople spend a lot of time thinking about the next job, the next customer, or the next challenge on…

A flat lay of a desk with stationery and notebook with writing 'insurance checklist', representing guide on questions to ask when buying contractor insurance
Contractor Guides Contractors 24 Aug 2026

7 things to ask before buying contractor insurance

Buying contractor insurance isn’t exactly the most exciting item on your to-do list.  When you’re focused on winning contracts, meeting…

Image of tradesman leaning against white van looking at insurance quotes on his phone, representing article discussing cheap tradesmen insurance
Trades Trades Life 28 Jul 2026

Cheap trades insurance: how low is too low?

When you’re running your own trades business, it’s only natural to try and keep costs to a minimum. But for…

Photo of protest crowd in london, representing article on loan charge review scandal
Contractors News 15 Jul 2026

Why the Loan Charge scandal isn’t going away

In the late 1990s, loan-based remuneration schemes began to emerge before becoming widespread among contractors and freelancers during the 2000s.…

Image of tradesman's arm being bandaged, representing article on employers' liability insurance for tradespeople
Trades Trades Life 07 Jul 2026

Do tradesmen need employers’ liability insurance?

If you’re a tradesman running your own business, you might assume employers’ liability insurance only applies to corporate companies. But…

Contractors News 19 Jun 2026

The tax, pension and savings changes UK contractors need to keep on top of

The 2026/27 tax year might not be bringing one dramatic overhaul, but it marks the beginning of a multi-year shift…

Photo of dug out earth with construction worker on mini excavator, representing article on plant and machinery insurance
Trades Trades Life 01 Jun 2026

What is plant and machinery insurance?

From diggers and dumpers to cement mixers and compressors, plant and machinery are the backbone of many trades. Whether you’re…

Close-up of dates on a green calendar, representing article discussing claims made vs claims occurring in business insurance
Contractor Guides Contractors 26 May 2026

Simplifying insurance: what is claims made vs claims occurring

When you’re choosing insurance, you’ll often come across two terms: claims made and claims occurring. They both refer to the…

Tradesmen tools laid out on table, representing article on tool theft stories and keeping tools safe
Trades Trades Life 20 May 2026

Tool theft stories: tradespeople going beyond locks to keep tools safe

As tool theft continues to dominate headlines and social feeds, many tradespeople are no longer relying on standard security –…

Goodie bag from Powered Now Advice on Tap event, representing article on tradespeoples' concerns about tool insurance claims
Trades Trades Life 15 May 2026

Powered Now ‘Advice on Tap’: trade talk and tool theft troubles

Powered Now’s landmark event brings together tradespeople of all backgrounds. But conversations highlight the ongoing issue of tool theft, the…

Photo of builders discussing construction plans, representing article on what professional indemnity means for tradespeople
Trades Trades Life 28 Apr 2026

What is professional indemnity for tradespeople?

Many tradesmen assume professional indemnity is only for people with a desk job. But in reality, if your work involves…

Image of two builders carrying construction materials, representing article on do subcontrctors need their own insurance
Trades Trades Life 15 Apr 2026

Do subcontractors need their own insurance?

Knowing whether subcontractors need their own insurance can be confusing. Whether working in construction, roofing, plumbing, electrical work or specialist…

Image of construction hard hats representing a guide to what insurance a tradesman needs
Trades Trades Life 31 Mar 2026

What insurance does a tradesman need?

Insurance sounds like a good idea, but how do you know what insurance you need as a tradesman? No two…

Photo of a presentation screen at an event held by Kingsbridge on the JSL legislation and what it means for recruitment agencies
Partner News Partners 30 Mar 2026

What JSL will mean for you: Five lessons from our expert panel

Earlier this month Kingsbridge brought together a panel of industry experts to discuss the implications of the government’s new JSL…

Builder working on a house extension roof, representing a guide to contract works insurance for tradespeople including what it covers
Trades Trades Life 17 Mar 2026

What is contract works insurance?

However big or small your construction project is, contract works insurance could be a lifesaver if something happens. When you’re…

Image of bricklaying representing article on who needs trades insurance and what it covers
Trades Trades Life 10 Mar 2026

Who needs trades insurance?

If you work in the trades, chances are you’ve already heard people chatting about tradesman insurance, but have been left…

Calendar with date circled, representing guide on what a retroactive date is in professional indemnity insurance
Contractor Guides Contractors 26 Feb 2026

Professional indemnity insurance: what’s a retroactive date

Whether you’ve just taken out a professional indemnity policy or you’re shopping for new business insurance, chances are you’ve come…

HMRC Making Tax Digital campaign asset, representing article disucssing the upcoming changes for sole traders April 2026
Contractor Guides Contractors 16 Feb 2026

A ‘Making Tax Digital’ wake-up call for sole traders

The way Britain pays tax is entering its biggest modernisation in a generation, with Making Tax Digital (MTD) for Income…

Photo of HMRC London offices representing article discussing the Employment Rights Act 2025 being law, what changes it brings and what businesses need to do now
Partner News Partners 22 Jan 2026

Employment Rights Act 2025 ‘brings world of work into 21st century’

Big changes to the world of work have been on the horizon for a while and the Royal Assent of…

HMRC Self Assessment tax return letter for 2025 tax year sent to UK taxpayer with UTR and NINO
Contractor Guides Contractors 16 Jan 2026

Online Self Assessment tax return deadline: what to know for 2026 (and beyond)

If you’re required to file a Self Assessment tax return for the 2024/25 tax year, the deadline to submit it…

Contractor Guides Contractors 01 Jan 2026

What is the difference between a sole trader and a limited company?

One of the big questions for any contractor when they first set up as self-employed is whether you should operate as a…

Image of sparks caused by power tools, representing article on what makes a trade high risk for insurance
Trades Trades Life 18 Dec 2025

Trades cover: who’s considered high risk for insurance

If you’re in the trades, you already know the job isn’t without its risks. But did you know those risks…