| L'Assomption | |
| Settlement Type: | Regional county municipality |
| Coordinates: | 45.8°N -99°W |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Type2: | Region |
| Subdivision Name2: | Lanaudière |
| Established Title: | Effective |
| Established Date: | January 1, 1983 |
| Seat Type: | County seat |
| Seat: | L'Assomption |
| Government Type: | Prefecture |
| Leader Title: | Prefect |
| Leader Name: | Chantal Deschamps |
| Area Total Km2: | 285.40 |
| Area Land Km2: | 255.65 |
| Population Footnotes: | [1] |
| Population Total: | 124,759 |
| Population As Of: | 2016 |
| Population Density Km2: | 488.0 |
| Population Blank1 Title: | Change 2011–2016 |
| Population Blank1: | 4.1% |
| Population Blank2 Title: | Dwellings |
| Population Blank2: | 50,828 |
| Timezone: | EST |
| Utc Offset: | −5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | −4 |
| Postal Code Type: | Postal code(s) |
| Area Code: | 450 and 579 |
L'Assomption (The Assumption) is a regional county municipality in the Lanaudière region of Quebec, Canada. The seat is L'Assomption. L'Assomption is located directly north of the city of Montreal.
It is named for the L'Assomption River, which flows through the region from the north before emptying into the Saint Lawrence River in the south of the region at Repentigny.
There are 5 subdivisions within the RCM:
| Canada Census Mother Tongue - L'Assomption Regional County Municipality, Quebec | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Census | Total | ||||||||||||||||||
| Year | Responses | Count | Trend | Pop % | Count | Trend | Pop % | Count | Trend | Pop % | Count | Trend | Pop % | ||||||
| 113,485 | 2.0% | 91.6% | 1,760 | 8.0% | 1.4% | 595 | 9.8% | 0.56% | 7,990 | 67.5% | 6.5% | ||||||||
| 111,225 | 7.3% | 94.03% | 1,630 | 21.6% | 1.38% | 660 | 97.0% | 0.56% | 4,770 | 38.7% | 4.03% | ||||||||
| 103,700 | 3.3% | 95.30% | 1,340 | 21.3% | 1.23% | 335 | 42.6% | 0.31% | 3,440 | 135.6% | 3.16% | ||||||||
| 100,400 | 2.4% | 97.29% | 1,105 | 22.7% | 1.07% | 235 | 30.9% | 0.23% | 1,460 | 9.8% | 1.41% | ||||||||
| 98,090 | n/a | 96.94% | 1,430 | n/a | 1.41% | 340 | n/a | 0.34% | 1,330 | n/a | 1.31% | ||||||||
Highways and numbered routes that run through the municipality, including external routes that start or finish at the county border:[2]