The basic answer to “what is a young horse called” is a foal – any baby horse of either sex under 12 months old is a foal. A male foal is called a colt and a female foal is called a filly, and as they grow you may also hear terms like suckling, weanling, and yearling used for specific ages and stages.
If you love foals and are already thinking about the perfect baby horse name, understanding the correct terms for each life stage will help you sound like a pro in the barn.
Quick Comparison: Foal vs Weanling vs Yearling vs Colt vs Filly
| Term | Sex | Typical Age Range | Key Detail |
|---|---|---|---|
| Foal | Either | Birth to under 1 year | General term for any baby horse. |
| Suckling | Either | Birth to weaning (about 4–7 months) | Foal that is still nursing from the mare. |
| Weanling | Either | Weaning to under 1 year | Foal that has been weaned but is not yet a year old. |
| Yearling | Either | 1 to under 2 years | Young horse of either sex between one and two years old. |
| Colt | Male | Birth to under 4 years | Young male horse; often used from weaning up to 3–4 years. |
| Filly | Female | Birth to under 4 years | Young female horse; becomes a mare at about 4 years. |
| Mare | Female | 4+ years | Adult female horse. |
| Stallion | Male (not castrated) | 4+ years | Adult breeding male horse. |
| Gelding | Male (castrated) | Any age | Castrated male horse; often gelded between 6 months and 2 years. |
Main Baby Horse Terms (With Exact Ages)
Foal (Birth to Under 1 Year)
A foal is any young horse from birth until its first birthday, regardless of sex. This is the main term answer to “what is a young horse called.”
- Used for both males and females.
- After about one year of age, the horse is no longer called a foal and becomes a yearling.
Suckling (Nursing Foal)
A suckling is a foal that is still drinking milk from its mother.
- Applies from birth until weaning.
- Most foals are weaned between about 4 and 7 months of age.
Weanling (Weaned but Under 1 Year)
A weanling is a young horse that has been weaned off its dam but is still under one year old.
- Comes after the suckling stage.
- Still considered a foal, but “weanling” specifies that it is no longer nursing.
Yearling (1 to Under 2 Years)
A yearling is a horse of either sex that is between one and two years old.
- The horse is no longer a foal once it turns one.
- “Yearling” is purely an age term; it does not indicate sex.
Foal vs Yearling vs Colt vs Filly (Sex & Age Differences)
Colt (Young Male)
A colt is a young male horse, usually under four years old.
- Technically refers only to males, although many people mistakenly use “colt” for any young horse.
- A male horse is typically called a colt up until about 3–4 years old, depending on discipline.
Filly (Young Female)
A filly is a young female horse under about four years old.
- “Filly” is the female counterpart to “colt.”
- Once she reaches 3–4 years (often 4), she is generally called a mare.
When Do Colts Become Stallions or Geldings?
- Stallion: A non‑castrated male horse 4 years and older is called a stallion.
- Gelding: A castrated male horse of any age is called a gelding.
- Castration often occurs between about 6 months and 2 years for handling and temperament reasons.
So a colt that remains entire (not castrated) is usually called a colt until about age 4, then becomes a stallion. If he is castrated at any point, he is a gelding from then on, regardless of age.
When Does a Filly Become a Mare?
- A mare is an adult female horse, usually 4 years or older.
- A filly is a young female under roughly 4 years.
In many contexts, the change from filly to mare is made at 4 years, although racing definitions may vary slightly by country and breed.
Life Before Birth: Gestation in Horses
The life of a young horse starts long before it’s called a foal. A female horse, or mare, is pregnant for about 11 months on average (roughly 340 days) before giving birth.
- When a mare is pregnant, she is said to be “in foal.”
- When she gives birth, the process is called “foaling,” and the newborn is said to be “foaled.”
- Foals can stand and run very shortly after birth, an important survival trait in the wild.
Everyday Usage vs Technical Definitions
In casual conversation, people may use some of these terms a bit loosely:
- Calling any young horse a “colt,” even if it’s a filly, is a common mistake.
- “Foal” is sometimes used up to the yearling stage in informal talk, even though technically a yearling is over one year old.
- Definitions can differ slightly in racing or specific breed registries (for example, some racing authorities may treat horses as colts/fillies up to 5 years).
If you’re naming a young horse, it helps to use the correct term for its age and sex, especially when choosing specialized mare names or powerful stallion names later in life.
FAQ About Baby Horse Names and Terms
What is a baby horse name people use most often?
The most common general baby horse name term is foal for any horse under one year, regardless of sex. If you want to be more specific, you would say a colt (male foal) or filly (female foal).
Is a foal the same as a weanling?
Every weanling is a foal, but not every foal is a weanling.
- Foal: Any horse under one year old.
- Weanling: A foal that has been weaned (no longer nursing) but is still under one year.
What is the difference between a colt and a foal?
Foal is a general term for any baby horse under one year old of either sex. Colt refers specifically to a young male horse, typically from foalhood up to about 3–4 years of age. A baby male under one year is both a foal and a colt; a baby female under one year is a foal and a filly, but never a colt.
When should I start using “mare” instead of “filly”?
Most horse resources define:
- Filly: Female horse under about 4 years old.
- Mare: Female horse 4 years and older.
Some owners might switch a bit earlier (around 3 years) depending on maturity and discipline, but using “mare” at 4 years is widely accepted.
Ready to Name Your Young Horse?
Now you know that the correct answer to “what is a young horse called” is usually foal, with more specific terms like suckling, weanling, yearling, colt, and filly describing age and sex in more detail. If you’re welcoming a new foal to the barn, this is the perfect time to pick a memorable, meaningful name.
Explore our curated lists of creative, cute, and classic baby horse names to find the perfect fit for your new foal.