| Province: | NS |
| Type: | Route |
| Route: | 203 |
| Length Km: | 83 |
| Length Round: | 0 |
| Length Ref: | [1] |
| Direction A: | West |
| Direction B: | East |
| Terminus A: | / Trunk 40 in Carleton |
| Junction: | in Shelburne |
| Terminus B: | in Shelburne |
| Counties: | Yarmouth, Shelburne |
| Previous Type: | Route |
| Previous Route: | 202 |
| Next Type: | Route |
| Next Route: | 204 |
Route 203 is a collector road in the Canadian province of Nova Scotia.
It is located in Shelburne and Yarmouth Counties and runs through a sparsely populated area including Argyle Municipality from Shelburne at Trunk 3 along the border of the Tobeatic Wilderness Area through Kemptville and connects to Nova Scotia Route 340 at Carleton. The village of East Kemptville is the only part of a municipality in Nova Scotia disconnected from the rest of the district by roads, and accessible only from other districts via Highway 203.
Route 203 is considered the loneliest road in the province because it has the longest uninhabited stretch of any paved highway in Nova Scotia.[2]