| State: | NM |
| Type: | SR |
| Route: | 456 |
| Map Custom: | yes |
| Map Notes: | NM 456 highlighted in red |
| Length Mi: | 58.784 |
| Length Ref: | [1] |
| Direction A: | West |
| Direction B: | East |
| Terminus A: | in Folsom |
| Junction: | in Folsom |
| Terminus B: | west of Kenton, OK |
| Counties: | Union |
| Previous Type: | NM |
| Previous Route: | 455 |
| Next Type: | NM |
| Next Route: | 457 |
State Road 456 (NM 456) is a 58.784adj=midNaNadj=mid state highway in northeast New Mexico. NM 456's western terminus is in Folsom, New Mexico at NM 325, and the eastern terminus is at the Oklahoma state line west of Kenton, Oklahoma. At the state line, it becomes Oklahoma State Highway 325 (SH-325).
NM 456 parallels the Cimarron River for its entire length. It does not leave Union County. It is a former routing of U.S. Route 64 (US 64). Seventeen consecutive miles of it are unpaved, as per signs at each end of the unpaved stretch; their main purpose is to warn of potential impassibility in inclement weather. The stretch does have two spots of pavement, nevertheless: one about 8miles in from the west, which is only about 100feet long, and one about 14miles in from the west, which often confuses drivers since it is so near to the end of the advertised length (its pavement lasts about 0.5miles). The drive has some nice scenic views, including one reminiscent of Colorado's Garden of the Gods; but its remoteness is not amicable to tourists having automobile breakdowns.