The 4-inch rule, explained

Why the United States bans the sale of small turtles, what the law actually says, and how to buy one legally.

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A musk turtle held in two hands, its plastron facing the camera.

In 1975 the Food and Drug Administration banned the sale of turtles with a shell under four inches long. The rule is still in force, it is federal, and it applies in every state. It is the single most important law for anyone buying a pet turtle in this country.

Why four inches

Turtles carry Salmonella on their skin and shells as a matter of course. It does not make them sick. It makes people sick, and in the early 1970s it was making a quarter of a million children sick every year. Small turtles were sold in dime stores, children put them in their mouths, and the shell size was simply the point at which a turtle stops fitting in a toddler's mouth.

The regulation, 21 CFR 1240.62, bars the sale, holding for sale, or any other commercial or public distribution of live turtles under four inches and of viable turtle eggs. The exception is for bona fide scientific, educational or exhibition purposes, and for export.

What it means when you shop

  • A hatchling red-eared slider is about an inch long. Selling one as a pet is illegal, however it is labelled.
  • Online sellers sometimes ask buyers to tick a box saying the turtle is for educational use. That does not make the sale legal for a pet.
  • Musk, mud and most map turtles barely reach four inches as adults, so legal animals of those species are already grown.
  • A breeder who raises hatchlings to four inches before selling them is doing it right, and will charge for the year of care.

State laws on top

About a dozen states ban the sale of turtles at or under four inches in their own code, and a few go further. Arkansas uses a six-inch line. Some states prohibit particular species, protect native ones from sale, or require a permit. The FAQ on our home page lists the questions to ask, and each species guide carries its own legal note.

What to do

Buy from a breeder who can tell you the hatch year and show you the animal's size. Ask how they comply with the four-inch rule. If the answer is a form you sign, walk away. A turtle bought at four inches has survived its riskiest year and is far more likely to live out the decades ahead of it.

A pond turtle looking up through the water of a home tank.
A 1789 engraving of a turtle seen from above, by James Heath.

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