New Hampshire elected its members August 18, 1820.
| District | Incumbent | This race | ||||
|---|---|---|---|---|---|---|
| Member | Party | First elected | Results | Candidates | ||
| Josiah Butler | Democratic-Republican | 1816 | Incumbent re-elected. | √ William Plumer Jr. (Democratic-Republican) 16.6% √ Nathaniel Upham (Democratic-Republican) 16.5% √ Josiah Butler (Democratic-Republican) 16.2% √ Matthew Harvey (Democratic-Republican) 14.9% √ Aaron Matson (Democratic-Republican) 14.2% √ Thomas Whipple Jr. (Democratic-Republican) 10.6% Arthur Livermore (Democratic-Republican) 5.9% Levi Jackson (Federalist) 2.7% Clifton Clagett (Democratic-Republican) 2.2% | ||
| Nathaniel Upham | Democratic-Republican | 1816 | Incumbent re-elected. | |||
| Clifton Clagett | Democratic-Republican | 1802 1804 (Retired) 1816 | Incumbent lost re-election. New member elected. Democratic-Republican hold. | |||
| Joseph Buffum Jr. | Democratic-Republican | 1819 | Incumbent retired. New member elected. Democratic-Republican hold. | |||
| William Plumer Jr. | Democratic-Republican | 1819 | Incumbent re-elected. | |||
| Arthur Livermore | Democratic-Republican | 1816 | Incumbent lost re-election. New member elected. Democratic-Republican hold. | |||