Contractors IR35

Shanks ruling reminds ‘outside IR35’ contractors of unfettered substitution’s value

Unfettered. Freely exercisable. Without limiters. Anything less in a sub clause just won’t do (to keep personal service from biting). …

Simon Moore, Managing Director at Moore News Ltd, journalist specialising in freelancing, small business, self-employment, and IR35 topics. by Simon Moore
Exam invigilator image. Discussing Mrs J Shanks IR35 ruling on right of substitution

Unfettered. Freely exercisable. Without limiters. Anything less in a sub clause just won’t do (to keep personal service from biting). 

An employment tribunal finding an invigilator to be a “worker” underscores the importance for contractors of having an unfettered right to substitute. 

If ‘outside IR35’ is the goal, a sub clause must not be like the invigilator’s was – actionable only when services cannot be performed, such as due to illness. 

And if ‘outside IR35’ contractors still have doubts due to right-of-substitution curbs like illness, iron out the clause, or exercise it – even just for a short time.   

Kingsbridge yesterday issued this three-fold guidance (‘don’t use an illness-only sub clause; revise it, or action it’), in light of the ruling for the invigilator, Mrs J Shanks.  

‘Shanks v SQA is primarily a holiday pay case’ 

She has won her case, Mrs J Shanks V Scottish Qualifications Authority (SQA), which was “primarily a claim for holiday pay,” states the ruling, released on Thursday (22nd May 2025).  

The case heard many aspects of Shanks’ contract and “day-to-day” working practices at SQA, because to be entitled to holiday pay, she had to prove “worker” status. 

One of the three elements in the statutory definition of a “worker”, which dominated the hearing, is whether the person is required to do the work personally.  

‘An unpoliced Right of Substitution, because we’re not bothered by a no-show’ 

In trying to prove it didn’t owe Shanks holiday pay for invigilating in 2024, SQA all but said she “had a Right of Substitution (RoS) which they didn’t police”. 

This is how Kingsbridge’s IR35 Consultancy Manager Matt Tyler sums up SQA’s argument against personal service to employment judge Muriel Robison. 

Indeed, SQA said “they are not bothered by someone who does not turn up”; that invigilators could “swap shifts,” and if they swap, it needn’t be notified. 

‘Overly fettered, with limiters’ 

“But actually, Shanks could only invoke her RoS in limited circumstances or with an overly fettered pool of replacements to choose from,” said Mr Tyler, citing the ruling.  

“Invigilators could not undertake work if they didn’t have a SQA contract. They needed allocation to a centre, prior training, and know-how of the ‘set-up.’ 

“Fettering the right to substitute so it’s only usable in certain circumstances, such as due to illness which Judge Robison found was the case for Shanks, is, in effect, putting limiters on the [RoS]. 

“Fettering the RoS also limits the contracting parties’ ability to utilise whatever resource they deem appropriate to undertake the work. 

“And collectively, these limiters go some way to suggesting a personal service requirement, even if the engager is just trying to ensure continuity of services.”  

Frances Lewis, of law firm Osborne Clark, agrees, but points out that ‘Shanks’ is an employment tribunal case, making it not legally binding on future cases.  

‘RoS must be unfettered to negate personal service’ 

The law firm’s Head of Contingent Workforce, Ms Lewis told Kingsbridge: “In terms of contractor tax status, the [Shanks] case serves to reiterate the point that for a Right of Substitution to negate personal service, it must be unfettered and freely exercisable by the individual. 

“Having a right to use a substitute who has been pre-vetted by the client, or a right which is exercisable only where the contractor cannot perform the services, will not be enough to remove personal service.” 

John Chaplin, of professional services firm BDO, issued a large caveat of his own, despite also signalling that fettering equates to trouble if ‘outside IR35’. 

‘Interesting from the potential impact on IR35’ 

“[Shanks] is an employment law [case] rather than a tax case. While it might be interesting from the impact it may have on IR35, it is not automatic as there is no direct map across,” he began. 

“For example, in the ‘Pimlico Plumbers case’ [which was relied on heavily by SQA], plumbers were held to be workers for employment law but not employees for tax. So ‘Shanks’ should be taken in that light by Personal Service Company contractors.   

“[That said]…. [Judge Robison’s] findings regarding substitution…reinforce the need for any substitution to be ‘unfettered’.” 

‘Restrictions fatally damage the argument that substitution exists’ 

BDO’s Employment Tax Partner, Mr Chaplin continued to Kingsbridge: “Any restrictions to substitution, put on by the hirer, will weaken if not fatally damage the argument that substitution exists.   

“The ‘Shanks’ case reinforces the message that contractors need to ensure that the ability to substitute is real, without restriction, and not just a contractual clause.”  

In the ruling, Judge Robison said the “clear” evidence showed “no unfettered right to substitute”, as invigilators would have to inform the chief invigilator, “at the very least”. 

‘Deliveroo’ 

This establishment of an unfettered right to substitute then undermined SQA’s ‘Deliveroo argument’. 

The authority claimed that, like the food riders in the 2016 Deliveroo case, there was no policing of a substitute should invigilators choose to use one, and no penalty or adverse consequences where substitution was actioned. 

But the judge said: “I do not consider that the position of the Deliveroo rider can be said in general to be analogous to the role of the invigilator, not least because it was apparent that there was clearly an unfettered right to substitute in that case.” 

The “evidence” before the tribunal showed Shanks enjoyed a right of substitution “only when the contractor is unable to carry out the work”, which is “indicative of personal service”. 

‘Unfettered RoS is crucial, both in the written terms and in reality’ 

Kingsbridge’s Matt Tyler says the message from the tribunals is therefore clear, particularly (albeit indirectly) to ‘outside IR35’ contractors looking to cement their commercial position. 

He advises: “It is crucially important [to keeping ‘inside IR35’ at bay] that there is as unfettered as possible right to provide a substitute enshrined in the engagement, both in the written terms and in the reality of how the contractor is operating.  

“‘Outside IR35’ contractors must always remain free and able to supply a substitute at any given point for any reason they deem necessary. This may include illness but should NOT be limited to JUST illness.  

“Where there is doubt as to the authenticity of a right of substitution, confirm the position and, if necessary, invoke that right even if it’s for a nominal period.” 

Getting support with IR35

Navigating IR35 legislation and ensuring compliance can be challenging for contractors and businesses alike. At Kingsbridge we offer tailored support, including expert guidance on IR35 status assessments, compliance strategies, and risk mitigation. Our team is dedicated to helping contractors and businesses understand and adapt to the evolving tax landscape.

We also offer a range of flexible business insurance options to support contractors, including Professional Indemnity, Public Liability, and Employers’ Liability cover, as well as add-ons like Cyber Insurance and Director and Officer’s Liability.

To find out more, get a quote or contact us to speak to an in-house expert today. 

 

Simon Moore, Managing Director at Moore News Ltd, journalist specialising in freelancing, small business, self-employment, and IR35 topics.

Simon Moore, Managing Director at Moore News Ltd

Simon Moore is a journalist with NCTJ-approved journalism training, who has worked inside the newsrooms of local, consumer and national media titles.

He today writes news and features for trade publications specialising in freelancing, small business and the self-employed. Simon’s articles have been linked to by The Daily Telegraph and the biggest newspaper website in the world, MailOnline. He was appointed to be a judge at IPSE Freelancer’s Awards 2023.

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…