HMRC v Align Technology has narrowed the legal definition of “dental prosthesis.” It is not just an aligner story, and most labs have not clocked how far it reaches.
On 7 July 2026, the Upper Tribunal handed down its decision in HMRC v Align Technology. HMRC won. Clear aligners are now standard rated for VAT, not exempt.
If you make or supply orthodontic appliances, retainers, or even mouthguards and occlusal splints, this matters. Not just for aligners. For a lot more than aligners.
Align had been treating Invisalign supplies as exempt “dental prostheses” under Schedule 9 of the VAT Act. The First Tier Tribunal (FTT) agreed with them in 2025. HMRC appealed. The Upper Tribunal overturned it.
The whole case turned on the definition of “dental prosthesis.”
The Tribunal looked at dictionary definitions, EU guidance, case law from completely different fields, a colostomy bag case, a disability discrimination case about ankle pins, and came to a clear conclusion. A prosthesis replaces something missing or broken. It performs the function of a part of the body that isn’t there or doesn’t work.
HMRC’s position, which the Tribunal accepted, is that an aligner doesn’t replace anything. It moves teeth that are already there into a better position.
Dental prostheses are “artificial items which replace missing or damaged teeth.” Aligners don’t do that, so they no longer qualify for exemption.
One distinction is worth being precise about, and this is really important because it is easy to conflate the two.
The dentist’s clinical exemption for providing treatment is untouched by this ruling. A dentist or orthodontist providing a course of orthodontic care, assessing the patient, planning treatment, fitting and adjusting the appliance, remains exempt as the supply of medical care by a registered professional. That remains unchanged.
What has changed is the VAT treatment of the appliance itself, being classed as a product. When a lab supplies an aligner, retainer, splint or similar item as a good, that supply now sits outside the prosthesis exemption unless it replaces missing or damaged tooth structure, according to the HMRC ruling. The treatment stays exempt. The product the lab makes and sells does not, unless it is one of the traditional prosthetic items. This is a lab side VAT change, not a change to how clinical fees are treated in practice, although this could change if HMRC are looking for other areas to gain more tax receipts.
Here’s the bit that affects us all as a profession. The Tribunal wasn’t ruling on Invisalign specifically. It was ruling on what the word “prosthesis” means in law. That interpretation now applies to anyone supplying anything described as a dental prosthesis. The acid test used by HMRC is simple. What does the appliance actually do?
Once you apply “does it replace, or does it just support, protect, or move” as the test, a lot of things we’ve all quietly assumed were exempt start looking shaky.
Think about what a dental lab actually makes in a given month. Crowns, bridges, dentures: clearly exempt, no argument, they replace missing or damaged tooth structure. I cannot see HMRC coming for those.
But what about:
Most retainers hold teeth in position after orthodontic treatment. They don’t replace anything, unless they temporarily include a tooth or pontic whilst a more permanent bridge or implant crown is provided. Same logic as aligners applies directly.
These protect teeth from wear, they don’t replace missing or damaged teeth. On the Tribunal’s own reasoning, an occlusal splint looks more like a colostomy bag than a prosthetic limb. It performs a function, but not the specific function of replacing a missing body part. The Northern Ireland case the Tribunal leaned on is helpful here: “Many artificial aids clearly could not be classed as prostheses, such as wheelchairs, zimmer frames or dialysis machines.” It could be argued that a splint sits in that category, not the prosthesis category.
Same as aligners. They move or guide growth, they don’t replace tooth structure.
They are protective, not a replacement of missing or damaged teeth. There has been a lot discussed about them being PPE, Personal Protective Equipment, so it is worth being clear that PPE classification and VAT exemption are two completely separate things. Sports mouthguards are regulated as PPE for product safety purposes, meaning a lab making them has to comply with conformity testing and certification requirements from a notified body. That is a safety law question, not a tax one. The only VAT relief PPE has ever had was a temporary Covid measure, zero rating protective equipment from May to October 2020, which ended and reverted to standard rate. HMRC removed the guidance for it entirely in 2025 because it no longer applies. Being classed as PPE gives a sports guard no VAT exemption of any kind. It still has to pass the same test as everything else on this list. Does it replace a missing or damaged tooth, or does it protect one that is already there?
The common theme is that HMRC have gone hard on the English definition of “dental prosthesis.” If the appliance’s job is to move, hold, guard, or protect, rather than replace what’s missing, this ruling suggests it’s standard rated. If its job is to physically stand in for a tooth or teeth that aren’t there, it stays exempt.
What struck me reading the full judgment is that this isn’t a surprise conclusion and I had previously written about HMRC potentially looking deeper in dental treatments. The EU VAT Committee looked at this exact question back in 2015 and reached an almost unanimous view, 24 to 27 out of 29 member states, that “dental devices” sit outside the exemption. Their working paper drew the same distinction. A brace “does not substitute a body part… and cannot be covered by the literal meaning of the term dental prostheses.”
The FTT chose not to follow that guidance in 2025. The Upper Tribunal has now effectively restored it, giving it real weight alongside the Tribunal’s own reading of the dictionaries and case law.
There is a second, quieter signal too, it almost went unannounced. HMRC’s own VAT Notice 701/57, the guidance dentists and technicians should actually work from, was updated on 15 February 2024 to remove a reference to orthodontic appliances from its list of exempt dental prostheses. That is a full year before the FTT even heard the case, and more than two years before the Upper Tribunal ruled. HMRC had rewritten its own guidance long before it went anywhere near a courtroom. I only discovered this in my research of this recent ruling.
So the direction of travel has been visible for over a decade, and HMRC had quietly repositioned itself well before this case landed. It just took the tribunal process to force the point through the UK courts.
It goes without saying, I’m not a tax advisor nor a VAT specialist. Anyone reading this should get proper VAT advice before changing anything, but the practical shape of it looks like this.
VAT is self assessed. There won’t be a letter coming from HMRC telling you what to do. The obligation to get your VAT position right sits with the business, not with HMRC chasing you down. Waiting to be contacted by HMRC isn’t a sensible position, it’s a way of building up financial risk, because interest and penalties run from when VAT should have been charged, not from when someone notices.
This is now binding Upper Tribunal precedent. But it isn’t final by any stretch. Align could still go to the Court of Appeal, and some businesses may choose to take a considered, advised position around that uncertainty. But “wait and see” as a default, without engaging an advisor, isn’t a defensible strategy anymore.
It’s worth noting that Align itself stopped charging its UK customers on an exempt basis back in August 2025, nearly a year before this ruling landed, while the appeal was still pending. That is the largest orthodontic appliance company in the world taking a precautionary position rather than waiting for the final word. It is a reasonable indicator of how seriously a well advised business treats this kind of exposure.
The sensible starting point for any lab is a straight audit of the product list. Split it into two piles: things that replace missing or damaged tooth structure, and things that move, hold, or protect existing teeth. The first pile stays exempt. The second pile needs a conversation with your accountant about VAT treatment.
There is a second consequence that is easy to miss, and it is worth flagging separately because it can catch smaller labs off guard.
The UK VAT registration threshold is £90,000 of taxable turnover in any rolling twelve month period, checked at the end of every month, not once a year. Cross it and you have thirty days to register.
The important detail is that this threshold is based on taxable turnover, not on turnover that was previously VATable. Standard rated and zero rated supplies both count towards the £90,000. Exempt supplies never have. A lab that has treated its entire output as exempt dental prostheses, including retainers, splints and expanders, has never needed to watch this figure at all, because none of that turnover counted.
Once retainers, splints, expanders and similar appliances move to standard rated, that turnover starts counting towards the £90,000 for the first time. A small lab that has comfortably sat under the radar for years, because it assumed its whole product line was exempt, could find a meaningful chunk of its turnover suddenly counts towards a threshold it has never had to think about before. It is worth running the numbers now. There is also a forward looking test. If you have reasonable grounds to believe a large order will push you over £90,000 of taxable turnover in the next thirty days alone, registration is triggered immediately, not at year end.
Aligners are the headline because Align is the biggest name and the money involved is eye watering. But the reasoning in this judgment doesn’t stop at aligners. It’s a test about function, not a list of named products. Any lab that’s been treating retainers or splints as exempt on the basis that “well, it’s dental, and dental technicians make it” needs to look at this properly, not just nod at the aligner headline and move on.
The definitional question was never really about Invisalign and their VAT affairs. It was about what “dental prosthesis” means. Now we know. A lot of what sits in a typical lab’s product line, and a lot of what sits under that £90,000 threshold, was built on the assumption that the older, broader reading would hold.
Once again, for clarity, I am not a Tax or VAT expert, but I do like to stay on the right side of HMRC and I regularly speak with my accountant. Al Capone ran a criminal empire for years without the law laying a finger on him. What finally caught him out wasn’t the violence or the racketeering. It was his tax affairs, the one area he wasn’t paying attention to.
To close, there is a lot to unpack, a lot to be discussed as a profession and lots of questions to be asked with specialist advisors. I certainly don’t think we should be complacent and think it will go away.
Knowing your worth also means understanding what’s coming for it. Know Your Worth. Own Your Value.
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