The Franklin Block is a historic commercial building at 75 Congress Street in downtown Portsmouth, New Hampshire.

The main facade, facing Congress Street, is lined with commercial storefronts on the ground floor, separated by brick piers, with the main building entrance near the center, framed by fluted stone pilasters.

Second-floor windows are grouped in fours, the outer windows of each group set in segmented-arch openings, and the center two set in rectangular openings topped as a pair by a rounded arch of brick and stone.

On the third floor, windows are either singly or in pairs in rounded-arch openings, also formed out of brick and stone.

The block was built as part of a gradual westward expansion of the city's downtown in the late 19th century.