Hannibal Hamlin House, National Register of Historic Places residence in Bangor, United States

The Hannibal Hamlin House at 15 5th Street is a 2+1/2-story wood-frame building with a mansard roof added in 1870 that creates a full third floor. Its front section has flushboard siding while the rear ell is clapboarded, and the roof is covered in decoratively cut slate shingles with paired brackets in the eaves. A hip-roof porch on square posts with paired brackets spans the two-bay street facade, and the main entrance on the northeast side sits under a similar porch with a projecting vestibule.

The house was built between 1848 and 1851 by William T. Hilliard and became home to Vice President Hannibal Hamlin during Abraham Lincoln's presidency starting in 1862. The building later underwent a transformation when it was adapted for academic use.

The house served as the official residence for presidents of Bangor Theological Seminary from 1933 to 2007 after Hamlin's son donated the property. This role shaped the building as a center of academic leadership in the community.

The house stands on the northwest side of 5th Street, just south of Hammond Street, in a residential area west of downtown Bangor. It is a private building, so there are no regular visiting hours; the exterior, including the porch and slate roof, can be seen from the street.

The house was built between 1848 and 1851 by William T. Hilliard, a clerk of the local court and deputy collector of customs, before Hamlin bought it in 1862. Hamlin added the mansard roof and full third story in 1870, giving the Italianate frame house its present roofline.