How Do Racehorses Get Their Names? The Jockey Club Rules (and How to Name Yours)

A racehorse gets its name from its owner — but the name is only official once The Jockey Club approves it. Every Thoroughbred registered in the United States is named through The Jockey Club‘s registry under Rule 6 of the American Stud Book, and the name has to clear a specific set of constraints: 18 characters or fewer including spaces and punctuation, no duplication of a name already in use, and nothing protected for its place in racing history. You submit up to six choices in order of preference, and roughly three-quarters of first choices are approved. About 450,000 names are unavailable at any given moment. So the naming is yours; the sign-off is theirs — and knowing the rules before you fall for a name saves you the small heartbreak of watching your favorite bounce.

Who actually names a racehorse — and who has the final say

The owner names the horse. That sounds obvious until you count how many hands can be on the decision. In a partnership, the managing partner usually submits the name after the group has its say. In a syndicate, the operator often runs a member poll or takes suggestions and files the paperwork for everyone. Whoever does the typing, the name goes to the same place: The Jockey Club, which has kept the American Stud Book — the official Thoroughbred registry for the United States, Canada, and Puerto Rico — for more than a century. Naming lives in Rule 6 of that rulebook, and the registry reviews and approves every name before it can be used.

A foal can be registered before it has a name, on the strength of its parentage, DNA, and microchip. But it has to carry an approved name before it can start in a race, and The Jockey Club sets a deadline each year after which a late fee applies. The advice I’d give any first-time owner is the same either way: name early, and walk in with more than one name you’d be happy to see in the program.

The Jockey Club naming rules that trip people up

Most refused names aren’t refused for being offensive. They’re refused for being taken, or for breaking one of a handful of mechanical rules that catch new owners off guard. These are the ones worth knowing before you get attached:

Rule	What it means
18-character limit	The whole name — letters, spaces, and punctuation — can’t exceed 18 characters. “Secretariat” fits; a long clever phrase usually won’t.
Up to six choices	You list as many as six names in order of preference on one application; the registry works down the list.
No name in current use	A name already carried by a registered Thoroughbred is unavailable until it is released.
Protected names	Names of historically significant horses are retired and can’t be reused.
Living people	A living person’s name needs their written permission on file with The Jockey Club.
No vulgar or commercial names	Obscene, offensive, or trade and advertising names are refused.

Two of these do most of the damage. The 18-character limit quietly kills a lot of clever names — the wittier the idea, the more likely it runs long. And the no-duplicates rule is bigger than it sounds: with roughly 450,000 names unavailable at any time, the obvious choice built off a famous sire is very often already gone.

How to submit a name, step by step

The process is quick, and most of it happens online through The Jockey Club’s registry.

1. Make sure the foal is registered — parentage confirmed, DNA typed, microchip in. You can’t name a horse the registry doesn’t yet recognize.
2. Build a shortlist. The old tradition is to play off the sire’s and dam’s names; it isn’t required, but it’s half the fun.
3. Check availability against the registry’s Online Names Book before you fall for one. The Jockey Club also offers a free naming tool that suggests available options.
4. Submit up to six choices, ranked, through Interactive Registration.
5. Pay the naming fee — and file before the annual deadline to avoid the late charge.
6. Wait for approval. If all six are refused, you simply submit again.

About 75% of first-choice names are approved. Roughly 450,000 are off the table at any given time.

Why names get rejected — and the legends that slipped through

About three-quarters of first choices clear on the first try, which means a quarter don’t — usually because the name is already in use, or too close in spelling or sound to one that is. Consider an owner who submits the perfect pun off their colt’s sire, only to learn it was registered to a horse in California two years earlier. The name comes back refused, and they’re down to choices two through six, which they hadn’t thought as hard about. That is the whole case for loving your backups.

The rules still leave room for genuine wit, and that’s where the sport’s naming lore comes from. Owners have spent decades hiding jokes in plain sight — building a name from the sire and the dam that reads as one thing to the registry and another to anyone paying attention. The best ones are an inside joke between an owner and the racing form.

A horse’s name is the first decision of ownership you make entirely on your own. Treat it like one.

Why the name matters more than it looks

Naming is the first thing an owner does that the public actually sees. Long before the horse runs, the name is on the foal certificate, the work tab, the entries. It’s also, for most first-time owners, the first genuinely fun part of a process that is otherwise due diligence and writing checks. If you’re still deciding how to get into ownership, our guide to buying a racehorse covers the four ways in; if you want to know what comes after the name — the part that arrives every month — we’ve broken down what it actually costs to keep one. The name is free to dream about. Almost nothing else is.

Frequently asked questions

How many characters can a racehorse’s name be?

Eighteen, including spaces and punctuation, under The Jockey Club’s rules. That covers the entire name, so longer multi-word ideas often have to be trimmed before they’ll fit.

Who approves racehorse names in the United States?

The Jockey Club, through its registry of the American Stud Book. Owners submit names; the registry reviews each one against Rule 6 and either approves or refuses it.

Can two racehorses have the same name?

Not at the same time. A name in current use is unavailable, and names of historically significant horses are protected permanently. Names that fall out of use are eventually released and can be claimed again.

Can I name a horse after a person?

Only with their written permission on file with The Jockey Club if the person is living. Names of well-known people, brands, and trademarks are otherwise refused.

How many name choices do I get?

Up to six per application, ranked in order of preference. The registry works down your list — which is exactly why your second and third choices deserve real thought.