Head and body length of N. narica is 410-670 mm, tail length is 320-690 mm. Height at the shoulder is about 305 mm, and weights range from 3-6 kg. Males are usually larger than the females. The pelage is fairly long and fairly coarse. Coloration is reddish brown to black with yellowish to dark brown below. The muzzle, chin, and throat are usually whitish. The feet are nearly black, there black and gray markings on the face, and the semi-prehensile tail is banded. N. narica has a long, pointed muzzle. The forelegs are short, the hind legs long, and the tail is longer than the body.

N. narica is found mainly in wooded areas and forages both on the ground and in the trees. While travelling on the ground, the tail is held erect and the tip is curled. Probing of crevices and holes is done with the long, movable snout. N. narica is diurnal, but adult males are mostly active during the night. The quest for food can take them 1,500-2,000 meters each day, after which coatimundis find a tree to roost in for the rest of the night. During the season when fruit is abundant N. nasua eats almost nothing else. At other times of the year females and young will look for invertebrates on the forest floor and adult males prefer large rodents.

The social structure of N. narica usually consists of females and young up to two years of age in a loosely banded group of 4-20 individuals. Males over two years are solitary, except during the breeding season. At this time the males may enter the group of females and their other offspring, remaining completely subordinate to the adult females. The breeding season coincides with the greatest abundance of fruit due to the great amount of competition for food between the large males and the rest of the group. It may also deter the males from preying on the baby coatis during the time of year that their diets become primarily carnivorous.

N. narica breeds once each year and the gestation period is 10-11 weeks. When a female becomes pregnant she leaves the group and constructs a tree nest where she gives birth to between 2 and 7 offspring. The babies weigh 100-180 grams at birth, open their eyes at 11 days, and are weaned at 4 months. At five weeks old the babies leave the nest and join the group with their mother. They are fully grown at 15 months and reach sexual maturity at 2 years of age.

White-nosed Coati are found in Belize, Columbia (Gulf of Uraba), Costa Rica, El Salvador, Guatemala, Honduras, Mexico (except Baja California), Nicaragua, Panama, USA (S Arizona and SW New Mexico).