| State: | NH |
| Type: | NH |
| Route: | 84 |
| Map Custom: | yes |
| Map Alt: | Map of New Hampshire Route 84 |
| Map Notes: | Map of Rockingham County in southeastern New Hampshire with NH 84 highlighted in red |
| Length Mi: | 4.184 |
| Direction A: | West |
| Terminus A: | in Kensington |
| Direction B: | East |
| Terminus B: | in Hampton Falls |
| Previous Type: | NH |
| Previous Route: | 78 |
| Next Type: | NH |
| Next Route: | 85 |
| Counties: | Rockingham |
New Hampshire Route 84 is a 4.184adj=midNaNadj=mid secondary east–west state highway in Rockingham County in southeastern New Hampshire. The western terminus is in Kensington at New Hampshire Route 150. The eastern terminus of NH 84 is in Hampton Falls at U.S. Route 1.
NH 84 begins at an intersection with NH 150 in Kensington. After less than a mile, it crosses into Hampton Falls, heading eastward towards downtown. NH 84 crosses over Interstate 95 without an interchange (access via NH 101 or NH 107) and turns north, ending at US 1 just feet from the eastern terminus of NH 88.
NH 84 is known as Kensington Road in Hampton Falls and Lamprey Road in Kensington.