Border Collie Harness Size
Most adult Border Collies have a chest girth of about 23–30 inches, so size M in our harness fits most of them. Always measure your own dog first.
Typical Border Collie chest size
| Dog | Typical chest | Our usual size |
|---|---|---|
| Male | 24–30 in | M |
| Female | 23–28 in | M |
These are typical adult ranges from a published dog chest size guide, and your dog may differ.
A note for Border Collie owners
A thick double coat can add inches, so press the tape down to the body when you measure.
Check your exact size
Use the dog harness size calculator with your dog’s real chest and neck. Puppies need a new measurement as they grow.
Common questions
What size harness does a Border Collie need?
Most adult Border Collies fit size M in our harness, based on a typical chest of 23–30 inches. Other brands size differently.
How do I measure a Border Collie for a harness?
Wrap a soft tape around the widest part of the ribcage, just behind the front legs, then measure the neck where a collar sits.
Should I size up or down?
Choose the size where your dog’s chest sits closest to the middle of the range, so you can adjust both ways.
Breed sizes are typical ranges, not guarantees. Ask your vet about health concerns.