Distinctive plumage on male. Wing and tail design distinguishes female, non-breeding male and juveniles from other ducks.
Male has a dark brown head, throat, and nape. Neck sides, chest and central underparts are white. Gray scapulars and tertials with a black central stripe. Long and pointed central pair of rectrices. Female has light brown spotted or striped plumage with black or brown. Alar underwing coverts with light brown bars and lighter edges.
It is possible to recognize 2 different ages:
1st or 2nd year especimen: with varying amounts of juvenile feathers retained on body, tail, and wings. Juvenile greater coverts are retained. If tertials are retained, they are narrow and pointed, grayish brown with a dark center. Some or all rectrices may be retained juvenile feathers.
Adult especimen: with broad and square-tipped greater coverts. Pearl gray tertials with dark centers in males. Brown gray with dark centers in females.
Northern Pintail begin partial pre-breeding molt in October acquiring breeding plumage (both age types). During the early winter months, tertials, rectrices, and some body feathers may be actively molting.
Primaries: 10 per wing.
Secundaries: 16-17 per wing.