Massachusetts - Criteria: C (architecture/engineering)
| Old Cambridge Historic District |
| Old Cambridgport Historic District |
| Old Castle |
| Old Cemetery |
| Old Central Fire Station |
| Old Central High School |
| Old Centre Historic District |
| Old Chelmsford Garrison House Complex |
| Old Chestnut Hill Historic District |
| Old Churchyard Cemetery |
| Old City Hall |
| Old Colony Iron Works-Nesmasket Mills Complex |
| Old Colony Railroad Station |
| Old Corner Bookstore |
| Old Covered Bridge |
| Old Curtisville Historic District |
| Old Douglas Center Historic District |
| Old Farm |
| Old Garrison House |
| Old Harbor Reservation Parkways, Metropolitan Park System of Greater Boston |
| Old Harbor U.S. Life Saving Station |
| Old Harvard Yard |
| Old Hose House |
| Old Indian Meeting House |
| Old Jail |
| Old King's Highway Historic District |
| Old Lynn High School |
| Old Medford High School |
| Old Mill |
| Old Mill Site Historic District |
| Old North Cemetery |
| Old North Church |
| Old Post Office Building |
| Old Post Office Building |
| Old Public Library |
| Old Shephard Farm |
| Old Shipbuilder's Historic District |
| Old Ship Meetinghouse |
| Old Ship Street Historic District |
| Old South Church in Boston |
| Old South Meeting House |
| Old South Union Church |
| Old State House |
| Old State Mutual Building |
| Old Third District Courthouse |
| Old Town Bridge |
| Old Town Center Historic District |
| Old Town Farm |
| Old Town Hall |
| Old Town Hall |
| Old Town Hall Historic District |
| Old Town Historic District |
| Old Village Historic District |
| Old Weir Stove Company |
| Old West Church |
| Oliver House |
| Olmsted-Hixon-Albion Block |
| Olmsted Subdivision Historic District |
| Opposition House |
| Orange Center Historic District |
| Original Congregational Church of Wrentham |
| Orlando |
| Orne, Sarah, House |
| Orrock, Rev. John, House |
| Orvis Road Historic District |
| Osborn, Benjamin, House |
| Osborne, Prince, House |
| Osborn House |
| Osborn Street School |
| Osgood Bradley Building |
| Osgood, Col. John, House |
| Osgood Farm |
| Osgood Hill |
| Osgood, Samuel, House |
| O'Shea Building |
| Osterville Baptist Church |
| Otis Company Mill No. 1 |
| Otis, (First) Harrison Gray, House |
| Otis, (Second) Harrison Gray, House |
| Otis-Wyman House |
| Our Lady Help of Christians Historic District |
| Our Lady of Good Voyage Church |
| Our Mother of Sorrows Monastery and Retreat Center |
| Outing Park Historic District |
| Oxford-Crown Extension District |
| Oxford-Crown Historic District |
| Oxford Main Street Historic District |
| Oxford, The |
| Packard, Moses, House |
| Padanaram Village Historic District |
| Paddock Farm |
| Page, Christopher, House |
| Page, H. P., House |
| Page, Nathaniel, House |
| Page, Thomas D., House |
| Paine-Dodge House |
| Paine Estate |
| Paine Furniture Building |
| Paine Hollow Road South Historic District |
| Paine, Robert Treat, Jr., House |
Data from United States Park Service and Wikidata
