Common Boa constrictors are large bodied snakes that can reach 12ft in length, with females getting considerably larger than males. They are generally a cream-brown with darker brown saddles and with red-brown tail saddles.

Common boas are often confused with the true red tail boas (Boa constrictor constrictor); instead they fall under the category of central American boas, though are from no specific locality or region and may well be a cross between different locales.