Sealyham Terrier Weight & Growth Chart

Complete weight guide with growth charts for male and female Sealyham Terriers from puppy to adult.

Male Adult Weight

23–24 lbs

Female Adult Weight

19–21 lbs

Sealyham Terrier Weight Overview

Weight range for the Sealyham Terrier: 23–24 lbs overall. Males: 23–24 lbs. Females: 19–21 lbs.

Sturdy and powerful at 23 to 24 pounds and approximately 10.5 inches tall, they are low-set and substantial with a body that belies their calm demeanor.. Consult the growth chart below for typical weight progression by age.

Growth Chart

When Does a Sealyham Terrier Stop Growing?

Sealyham Terriers typically reach their full adult height of 10–10 inches by 12 to 15 months and their full adult weight of 23–24 lbs shortly after. Sturdy and powerful at 23 to 24 pounds and approximately 10.5 inches tall, they are low-set and substantial with a body that belies their calm demeanor..

Factors that influence growth include genetics, nutrition, and spay/neuter timing. Dogs spayed or neutered very early may grow slightly taller due to delayed growth plate closure.

Is My Sealyham Terrier Overweight?

To determine if your Sealyham Terrier is at a healthy weight (23–24 lbs target):

Rib test: You should be able to feel the ribs without pressing hard, with a thin layer of fat covering them
Waist check: Viewed from above, there should be a visible waist behind the ribs
Tuck-up: From the side, the abdomen should tuck up behind the rib cage

Their hard, wiry, weather-resistant outer coat with dense undercoat coat can mask weight gain, so hands-on assessment is essential. If your Sealyham Terrier is overweight, work with your veterinarian to develop a safe weight loss plan. Even a 10% reduction can reduce the risk of Retinal Dysplasia and other conditions.

Feeding Recommendation

Plan on 0.5–0.5 cups of premium dry food daily for your adult Sealyham Terrier, divided into morning and evening meals. Given this terrier breed's predisposition to Retinal Dysplasia, discuss dietary approaches that may help manage this risk with your vet. Sturdy and powerful at 23 to 24 pounds and approximately 10.5 inches tall, they are low-set and substantial with a body that belies their calm demeanor..

Weight by Age Table

Age	Male (lbs)	Female (lbs)
3 months	5.6–6.4	4.7–5.5
6 months	12.3–14.1	10.4–12.0
9 months	17.8–20.6	15.1–17.5
12 months	22.3–25.7	18.9–21.9

Frequently Asked Questions

Adult Sealyham Terriers weigh 23–24 lbs (males: 23–24 lbs; females: 19–21 lbs). Sturdy and powerful at 23 to 24 pounds and approximately 10.5 inches tall, they are low-set and substantial with a body that belies their calm demeanor..

Most Sealyham Terriers reach adult height of 10–10 inches by 12–15 months, with full body weight of 23–24 lbs achieved shortly after. Sturdy and powerful at 23 to 24 pounds and approximately 10.5 inches tall, they are low-set and substantial with a body that belies their calm demeanor..

For a Sealyham Terrier at healthy weight (23–24 lbs), you should feel ribs without pressing hard, see a defined waist from above, and notice an abdominal tuck from the side. Even modest excess weight stresses this small-sized breed's frame and can worsen conditions like Retinal Dysplasia.

Start with the food label's guidelines for your puppy's current weight and adjust based on body condition. Sealyham Terrier puppies should eat 3–4 meals daily until 6 months, then transition to twice daily. Given the breed's predisposition to Retinal Dysplasia, your vet may recommend specific dietary considerations. Target adult weight is 23–24 lbs (23–24 for males, 19–21 for females).

Poor weight gain in a Sealyham Terrier puppy warrants a vet visit. For a breed that should reach 23–24 lbs at maturity, slow growth can signal parasites (very common in puppies), underfeeding, food intolerance, or illness. Given this breed's hard, wiry, weather-resistant outer coat with dense undercoat coat, it can be hard to visually assess body condition–weigh your puppy weekly. Your vet will likely run a fecal test and blood work.