EquiDiaryHorse vaccination schedule (UK): flu boosters, tetanus, and the rules by discipline
Last reviewed 30 October 2026
The UK question is rarely "which vaccines". It's "when is the flu booster due" — and the honest answer is that it depends on what your horse does, because racing, affiliated sport and FEI competition run on three different intervals. Here is each one, and where they clash.
This is a summary of published rules, not veterinary advice. This page covers Great Britain. Vaccination protocols depend on the product used and on your horse's circumstances; your vet decides what applies. Discipline rules change between seasons — always check the current rulebook before you enter.
In the US? Read the US version instead — the AAEP core vaccines and USEF show rules.
In Australia? Read the Australian version instead — no flu vaccine at all, and Hendra in its place.
The UK list is shorter than the American one
If you have read an American vaccination guide and wondered why it lists rabies and West Nile virus, this is why: those diseases are not endemic here, and they are not part of the routine British schedule. In practice a UK horse is vaccinated against:
- Tetanus — recommended for every horse. The bacterium lives in soil and droppings, horses are among the most susceptible species, and the disease is usually fatal once established. No body mandates it, because it isn't contagious and competition rules exist to stop horses infecting each other — but "not mandated" is a long way from "not needed". A horse that never leaves the yard still needs it.
- Equine influenza — the one every rulebook is built around, and the reason most owners think about vaccination dates at all.
- Equine herpesvirus (EHV) — risk-based, decided with your vet. Common on yards with young or travelling horses.
- Strangles — also risk-based, and more on owners' minds than it was: the national surveillance scheme recorded 271 cases in 2024, 479 in 2025 and 290 in the first six months of 2026. A vaccine is licensed, but its label promises protection for only two months after the second dose; a study published in 2026 suggests closer to a year, and the maker has applied in Europe for a 12-month label. Whether it is worth it for your horse is a question for your vet.
February 2019: why the flu rules got stricter
On 6 February 2019 the BHA cancelled all British racing after the Animal Health Trust confirmed positive equine influenza tests from an active racing yard. What made it serious was not that flu appeared — it is endemic in the British horse population — but that the affected horses had been vaccinated. Racing stopped for six days, at least 23 fixtures were lost, and 174 yards went into lockdown; it was the sport's biggest shutdown since foot-and-mouth in 2001.
The lesson shaped the rules that followed, and it is worth stating plainly: vaccination reduces how much virus a horse sheds and how far an outbreak travels — it is not a personal force field. That is precisely why the response depended on knowing, quickly and exactly, which horses had been vaccinated when, and which yards they had visited. Records were the tool that reopened racing in six days rather than six weeks.
2026: the outbreak that tested the annual rule
Flu came back hard in 2026. A new variant of the H3N8 virus (Florida clade 1) arrived early in the year, and between late March and early September Equine Infectious Disease Surveillance counted 183 laboratory-confirmed outbreaks — 136 of them formally reported, across 57 counties.
How the sports responded shows the difference between a rule and advice. The BHA limited raceday access to horses from licensed training yards from 20 May to 28 August; six-monthly boosters were already its permanent rule. British Dressage, British Eventing and British Showjumping stepped up passport checks at venues and barred any horse whose vaccinations had lapsed — and all three strongly advised a booster for any horse last vaccinated more than six months earlier. Advised, not required: all three still ask only for a booster within 365 days (the intervals are set out below), but in an outbreak year a horse at the end of its twelve months is the one they worry about.
Three disciplines, three intervals
This is the part that catches people out, especially anyone whose horse does more than one thing:
| Where you compete | Flu booster interval | Before competing |
|---|---|---|
| Racing (Rules of Racing) | every 6 months, compulsory since 15 Jan 2023 | seven clear days |
| British Eventing, Showjumping, Dressage, Riding Clubs | annual (within 365 days) | not within 7 days |
| FEI (international) | 6 months + 21 days | none within 7 days of arrival |
Racing
The Rules of Racing are the strictest, and the least forgiving about arithmetic. For primary courses started from 2022, the intervals are V1–V2 at 21–60 days and V2–V3 at 120–180 days, followed by six-monthly boosters. The rule that hurts: if an annual booster exceeds 365 days, or any primary course interval is missed by even a single day, the record is invalid and the horse must restart the entire primary course before it can enter a racecourse. There is no discretion in it — a day late is a restart.
Affiliated sport
British Showjumping, British Dressage and British Riding Clubs require boosters within 365 days of the last vaccination. British Eventing joined them on 1 January 2026, having announced in December that six-monthly vaccinations would no longer be required — so if you are working from advice written before then, it is out of date. All of them apply the seven-day rule: a horse cannot compete within seven days of a vaccination.
FEI
International competition sits between the two: a dose within six months and 21 days before arrival, boosters never more than 12 months apart, and no vaccination within seven days of arrival at the event. A primary course started since 1 January 2024 is two doses 21 to 60 days apart and a third within six months and 21 days of the second; one started earlier keeps 21 to 92 days and seven months.
The FEI also wants the doses in its app. Since February 2025 the vet has had to enter each flu vaccination of an FEI horse in the FEI HorseApp as well as the passport, on the day and with the horse present. Events have checked those entries since 1 January 2026, with warnings only until 30 June; since 1 July 2026 a missing or incorrect entry can draw a CHF 100 fine. The same app is where the FEI wants the horse's temperature, taken twice a day for the three days before arrival and twice a day until it leaves the event. And since 26 January 2026 the FEI's Equipass app has put an FEI horse's passport, vaccinations included, on a phone — alongside the paper passport, which it does not replace.
The multi-discipline trap. An eventer that also does an FEI class, or a point-to-pointer that hunts and competes, is bound by the strictest rule that applies to it — not by the one it used last. An annual booster keeps a horse eligible for British Eventing and simultaneously ineligible for an FEI class in the same month. If your horse crosses codes, work to the six-month clock and stop thinking about it.
Why the calendar drifts
Almost nobody's vaccinations stay on the dates they were planned. The vet's visit moves, the horse is off-colour the week it was due, the second dose lands late and every subsequent date shifts with it. That is the real problem: the next due date depends on when the last dose actually happened, not on when it was meant to.
With racing counting in six-month steps, affiliated sport counting to 365 days, and both punishing a single day's overrun, "is he still in date for next month?" is only answerable if you know precisely when the last one went in — and, under the Rules of Racing, when every dose before it did too.
Questions people ask
What vaccinations does a horse need in the UK?
In practice, tetanus and equine influenza. Tetanus is recommended for every horse because the disease is almost always fatal and horses are highly susceptible, though no body mandates it. Influenza is the one competition rules are built around. Equine herpesvirus and strangles vaccination are risk-based, decided with your vet. Rabies, West Nile virus and the encephalomyelitis viruses are core recommendations in North America but are not part of the routine UK schedule, because they are not endemic here.
How often does a UK horse need a flu booster?
It depends entirely on what the horse does, and the disciplines do not agree. Under the Rules of Racing, six-monthly boosters have been compulsory since 15 January 2023. British Eventing, British Showjumping, British Dressage and British Riding Clubs require an annual booster — British Eventing dropped its six-monthly requirement on 1 January 2026. FEI competition requires boosters within six months and 21 days. None of them allow a horse to compete within seven days of a vaccination.
What happens if a flu booster is late?
Under the Rules of Racing the consequence is severe: if an annual booster exceeds 365 days, or any primary course interval is missed by even a single day, the vaccination record is invalid and the horse must restart the entire primary course before it can enter a racecourse. Affiliated sport is generally less punitive, but an out-of-date passport still stops a horse competing. Clinically, a lapsed course may need restarting rather than boosting — ask your vet.
Let the record do the arithmetic
EquiDiary works from what you logged, not from a fixed calendar. Record the vaccination when it happens — batch number, vet and all — and the next due date recalculates itself. When it comes due, you get an email. Everyone who cares for the horse sees the same history, and the passport lives in the horse's wallet, ready when the steward asks for it.
Start free for 3 monthsSources
- British Horseracing Authority — flu vaccination rules (six-monthly boosters, Rules of Racing)
- British Eventing — Equine Influenza Update (annual boosters from 1 January 2026, and the May 2026 outbreak advice)
- British Showjumping — Equine Influenza Update
- British Equestrian — FEI passports and flu vaccinations
- FEI — Vaccinations and the 2026 Veterinary Regulations
- FEI — HorseApp vaccination module, horse health requirements (temperatures) and Equipass
- British Eventing — Competing internationally (the CHF 100 HorseApp fine from 1 July 2026)
- Equine Infectious Disease Surveillance — 2026 UK equine influenza outbreak summary
- British Dressage — Equine influenza update and BHA — raceday access limited to licensed yards (May 2026)
- Vet Times — Strangles vaccine offers year of immunity (July 2026; the Surveillance of Equine Strangles case figures)
Discipline rules are revised between seasons; check the current rulebook before entering, and confirm the protocol with your vet.
Check a horse's dates against the British Showjumping or FEI rule: the flu vaccination checker.
Also available in English (US, Australia) · Español (España, México) · Português (Portugal, Brasil) · Nederlands (Nederland, België) · Français (France, Belgique, Suisse) · Deutsch (Deutschland, Österreich, Schweiz) · Italiano (Italia, Svizzera)
Next: horse worming schedules — worm egg counts, tapeworm tests and winter redworm.