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PACS Thailand - Phangan Animal Care for Strays
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Advice 16 July 2026

How to tell if a street dog or cat has been sterilised

Look inside the ear. PACS applies a small tattoo to the inner ear of every animal it sterilises, cats and dogs alike, during the procedure itself. It is permanent, so an animal that has already been sterilised can be identified without being caught again. Sterilisation is free for stray and temple animals on Koh Phangan.

If you spend time on Koh Phangan you get to know particular animals: the dog outside your local shop, the cat that lives behind the restaurant. Sooner or later the question comes up. Has that one been neutered?

There is a way to check.

Check inside the ear for a tattoo

PACS applies a small tattoo to the inner ear of every animal it sterilises, during the procedure itself while the animal is already under anaesthetic. It is the same for cats and dogs.

It is permanent, so an animal that has already been sterilised can be identified by checking the ear rather than being caught again to find out.

In practice this is easier with an animal that already knows you and will let you close. If you cannot get near enough to look, report it anyway and let the team check.

Why PACS tattoos the ear

A sterilisation programme runs on limited surgical time. Marking each animal means the team can tell at a glance which ones have already been treated, rather than catching an animal a second time to find out.

Because the mark is permanent, it still works years later, when the people involved at the time have moved on.

Is sterilisation free on Koh Phangan?

Sterilisation is free of charge for stray and temple animals on Koh Phangan.

If you have your own pet you would like neutered, contact us to ask. Owned animals can sometimes be accommodated when clinic capacity allows, though strays always take priority.

How to report a street animal that needs neutering

If there is a street or temple dog or cat you see regularly with no tattoo in its ear, or you cannot get close enough to tell, let us know:

  • Use the Report a Stray in Need form, which is the quickest route
  • Or call the clinic on +66 (0)89 875 7513, Monday to Friday, 08:30 to 16:30. WhatsApp and LINE work on the same number

Include the location and a photograph if you can.

This is for street and temple animals. If the animal has an owner, that is a conversation to have with the owner rather than something to report.

Common questions

How do you know if an animal has been sterilised?

PACS applies a small tattoo to the inner ear during the sterilisation procedure. This is the same for cats and dogs. It is permanent, so an animal that has already been sterilised can be identified by checking the ear.

Are sterilisations free?

Sterilisation is free of charge for stray and temple animals on Koh Phangan.

Can I get my own pet neutered at PACS?

Contact PACS to ask. Owned animals can sometimes be accommodated when clinic capacity allows, though stray animals always take priority.

What should I do about a street animal that has not been sterilised?

Use the Report a Stray in Need form on the PACS website, or call the clinic on +66 (0)89 875 7513 between 08:30 and 16:30, Monday to Friday. Include the location and a photograph if you can. This is for street and temple animals. If the animal has an owner, speak to the owner.

PACS runs entirely on donations

There is no government funding. Every treatment, vaccination and sterilisation on this island is paid for by people who chose to help.