| Official Name: | Welsh Run, Pennsylvania |
| Settlement Type: | Unincorporated community |
| Pushpin Map: | Pennsylvania#USA |
| Pushpin Label: | Welsh Run |
| Pushpin Label Position: | top |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Pennsylvania |
| Subdivision Type2: | County |
| Subdivision Name2: | Franklin |
| Subdivision Type3: | Township |
| Subdivision Name3: | Montgomery |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Ft: | 515 |
| Coordinates: | 39.7647°N -77.8522°W |
| Postal Code Type: | ZIP code |
| Postal Code: | 17225 |
| Area Code: | 717 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 1190818 |
Welsh Run is an unincorporated community in Montgomery Township in Franklin County, Pennsylvania, United States. Welsh Run is located at the intersection of state routes 416 and 995, southeast of Mercersburg.[1]
A post office called Welsh Run was established in 1830, and remained in operation until 1906.[2] A large share of the first settlers being natives of Wales caused the name to be selected.[3]