Square and flat on top. Must be in proportion to the size of the body, with flat cheeks and free from wrinkles. The foreface is square and wide, shorter in length as compared to width or depth.
The ears are small, erect, and should be as close to the corners of the skull as possible.
The eyes are large, round, darkly colored, and set wide apart. An important characteristic of the ideal Boston Terrier is an alert, intelligent expression.
Deep and wide, with well-sprung ribs.
The shoulders slope well to the back, contributing to the Boston Terrier's notable stride. The forelegs are set moderately wide apart in line with the shoulder blades' upper tips.
The thighs are strong and well muscled, bent at the stifles and set true. The hocks are short to the feet, turning neither in nor out, with a well defined hock joint. Feet are small, compact and have short nails.
The feet are small and compact, with well-arched toes short nails.
Short and smooth, with a fine texture.
Additional coat colors, including blue, red, fawn and liver may be registered with the AKC, however, they may not be shown at AKC conformation events since they are not official standard colors. The "Colored Boston Terrier" is now recognized by the United Canine Association as a breed separate from the Boston Terrier.