Horse racing is one of the most followed sports on the planet, with millions of people from across the globe tuning in to watch the most iconic events on the calendar.
Three of the most followed races are the U.S. Triple Crown events, with the 2026 Belmont Stakes likely to rank as one of the most-watched equine events in 2026.
Legendary names of winning horses are as iconic as the race itself, with each etched into the history books for eternity.
However, what are the important factors that owners must take into account before giving an equine a name, and what rules are required to be followed when naming a runner?
Maximum Length
Horses will all need to follow the strict length requirement, with no name in the United States allowed to exceed 18 characters. This includes spaces and punctuation.
A clear workaround for this is to avoid spaces in desired longer names, so commentators read the horse's name the same way, regardless of whether there is a space in the name.
However, it is the Japanese-trained racehorse Sumomomomomomomomo who is regarded as having the longest name in history. This is because the name has 12 syllables.
Names Must Be Unique
Another key rule when naming a racehorse is the fact that a given name must be unique. Owners will have free rein to name their horse, but certain options will be unavailable. These will include horses that share the same name, who are in active training in the same country. Meanwhile, the names of iconic horses will also not be allowed.
This means that horses can’t be named in honor of runners in the Hall of Fame, or other previous champions who have had their names protected. Therefore, owners are unable to call their purchased horse Secretariat or Seabiscuit.
However, there are typically clashes with this rule due to rare exceptions. For example, Lossiemouth, winner of the 2026 Champion Hurdle at the Cheltenham Festival, was named in France, meaning that Lossiemouth, trained and brought in England, shares the same name. Fortunately, a commentator's nightmare was avoided in 2025 when both were originally set to line up in the Select Hurdle at Sandown.
Naming Horses After People
Horses also can’t be named after famous people. However, this rule can be breached if the Jockey Club gets written permission from a person that they are okay with the honour.
There is also a time frame on this rule, as famous historic figures have later seen equines named in their honour.
One of the most famous examples of this was Anthony Van Dyck, who was trained to success in the 2019 Epsom Derby by Aidan O’Brien.
The Classic-winning horse shared his name with a Flemish Baroque artist from the 1600s. Other notable figures to have been honoured by having a horse named after them in the modern day include Zlatan Ibrahimovic and Gustav Nyquist.
Commercialism
Horse racing is one of the biggest industries in the world, generating billions for economies across the globe. However, a major rule that shouldn’t be broken when naming a racehorse revolves around the fact that equines can’t be named after businesses.
Therefore, an owner can’t name a racehorse after their own company. However, there have been countless examples of creative ways to get around this general rule.
Banned Terms
As well as following major rules when naming a thoroughbred, owners must also avoid using certain terms in the naming process. This includes not being able to use the words ‘colt’, ‘filly’, and ‘mare’.
Furthermore, horses can’t include initials in their names, or numbers. However, for the latter, numbers in a spelled-out form can be included. An example of this comes in the form of the 1975 Cheltenham Gold Cup winner, Ten Up.
As well as certain words and numbers, horse names are also not allowed to include vulgar or offensive terms. Every name is assessed by the Jockey Club before being approved, but there are always some names that slip through the net. Among the named horses that have evaded the Jockey Club are Hugh Jass, Pat Myne, and Ima Pugg.
How Does the Naming Process Work?
The naming process is largely the same across the world, as owners will put forward between three and five different names for their runner. Each name will be assessed by the Jockey Club, to ensure that it follows the strict rules in place.
The organization will assess its database to ensure that the name isn’t already in use, while also assessing whether it is a name of a horse that can’t be honoured. Should it pass this test, and also avoid using banned terms and not include numbers, then it will be passed, and the horse will have its name for every start on the track.