Which allowance you get, and why it matters
Buy equipment and you cannot simply deduct it like a normal expense — you claim capital allowances, and which one applies changes the timing enormously. Sometimes all of it lands this year; sometimes a fraction a year for a decade.
Full expensing gives 100% on new main-rate plant and 50% on new special-rate assets. It is uncapped and permanent, and it is for companies buying new and unused assets only. The Annual Investment Allowance gives 100% on up to £1,000,000 a year, covers both pools, and is open to unincorporated businesses and to second-hand kit. For most practices the AIA does everything full expensing would have.
In this sector the spend that matters is typically digital radiography, ultrasound, anaesthetic machines, surgical tables, dental units, lab analysers and kennelling.
Imaging is plant. The room it sits in usually isn’t.
A CT or digital radiography unit is main-pool plant and, for a company buying new, gets full expensing at 100%. The lead-lined walls, the dedicated electrical supply and the ventilation are integral features in the 6% pool — and on an imaging installation the room can cost as much as the machine.
The same split applies to a theatre refit: the table and the anaesthetic machine are plant; the scavenging, the medical gas pipework and the lighting are not.
Kennels, and why they are argued about
Buildings do not qualify for plant and machinery allowances, but purpose-built animal housing has been treated as plant in some circumstances where it functions as apparatus of the trade rather than as premises. It is fact-specific and it is exactly the kind of thing worth establishing before the spend rather than defending afterwards.