| Province: | QC |
| Type: | QC |
| Route: | 143 |
| Maint: | Transports Québec |
| Map: | Route 143-QC.png |
| Length Km: | 165.8 |
| Length Round: | 1 |
| Length Ref: | [1] |
| Direction B: | North |
| Direction A: | South |
| Terminus B: | in Saint-François-du-Lac |
| Terminus A: | in Derby Line, Vermont |
| Previous Type: | QC |
| Previous Route: | 141 |
| Next Type: | QC |
| Next Route: | 147 |
| Counties: | Memphrémagog / Coaticook / Sherbrooke / Le Val-Saint-François / Drummond / Nicolet-Yamaska |
| Junction: | in Stanstead in Stanstead-Est in Hatley in Lennoxville (Sherbrooke) in Sherbrooke in Bromptonville (Sherbrooke) in Windsor in Richmond in Saint-Nicéphore (Drummondville) in Drummondville in Saint-Bonaventure |
Route 143 is a north/south highway on the south shore of the Saint Lawrence River, in the Centre-du-Québec and Estrie regions of Quebec. Until the mid-1970s when the province decided to renumber all highways other than autoroutes, it was known as Route/Highway 5. Its northern terminus is in Saint-François-du-Lac, at the junction of Route 132, and the southern terminus is in Stanstead, at the border with Vermont where the road continues past the Derby Line–Stanstead Border Crossing as U.S. Route 5 through Derby Line to New Haven, Connecticut.
Since Autoroute 55 closely parallels Route 143 for most of its length, much commercial traffic chooses the former. However, it is a very busy route and takes much traffic from the border to the Sherbrooke local area. Route 143 closely follows the Saint-François River between Sherbrooke and Ulverton.
The road is often in notoriously poor condition, since its original cement was laid directly on a gravel road in the mid-1920s. It has been extensively resurfaced to the point the pavement is now more than three feet thick in places, but it heaves extensively at every spring thaw.
| RCM or ET | Municipality | Km | Junction | Notes | |||
|---|---|---|---|---|---|---|---|
| Memphrémagog | Stanstead | 0.0 | 5 SOUTH: to Derby Line, Vermont | ||||
| 0.2 0.3 | 247 NORTH: to Ogden 247 SOUTH: to | ||||||
| 2.4 2.8 | 55 SOUTH: to in Derby Line, Vermont 55 NORTH: to Stanstead-East | ||||||
| Stanstead-East | 17.6 | 141 NORTH: to Ayer's Cliff 141 SOUTH: to Barnston-Ouest | |||||
| Hatley | 22.0 | (Overlap 0.6 km) | |||||
| Coaticook | Waterville | 36.2 | Rue Gosselin | EAST: to Waterville | |||
| 40.8 | (Overlap 6.0 km) | ||||||
| 44.1 | 147 SOUTH: to Compton | ||||||
| Sherbrooke | Lennoxville | 46.8 | (Overlap 6.0 km) | ||||
| Sherbrooke | 50.8 | 216 WEST: to Magog 216 EAST: to Stoke | |||||
| 51.9 | 112 WEST: to Rock Forest (Sherbrooke) 112 EAST: to Fleurimont (Sherbrooke) | ||||||
| Bromptonville | 58.3 | (East end) | 222 WEST: to Saint-Denis-de-Brompton | ||||
| 61.8 | Rue Laval | WEST: to | |||||
| Le Val-Saint-François | Windsor | 74.7 | 249 SOUTH: to Saint-François-Xavier-de-Brompton 249 NORTH: to Val-Joli | ||||
| Richmond | 90.2 | (Overlap 1.9 km) | |||||
| 91.3 | (Overlap 1.1 km) | ||||||
| 92.1 | (Overlap 1.9 km) | ||||||
| 92.4 | (Overlap 1.1 km) | ||||||
| Drummond | Saint-Nicéphore | 120.6 | (North end) | 139 SOUTH: to Wickham | |||
| Drummondville | 129.2 129.5 | (Overlap 0.3 km) | 122 EAST: to Saint-Charles-de-Drummond (Drummondville) 122 WEST: to Saint-Germain-de-Grantham (Drummondville) | ||||
| 131.9 132.2 | 20 EAST: to Saint-Cyrille-de-Wendover 20 WEST: to Saint-Eugène | ||||||
| Saint-Bonaventure | 148.8 | (East end) | 224 WEST: to Saint-Guillaume | ||||
| Nicolet-Yamaska | Saint-François-du-Lac | 165.8 | |||||