Ontario · Census Agglomeration
Sarnia by the numbers
Sarnia is Canada's 44th largest metro area, home to about 109K people, growing slower than the country since 2021 (+7.6% vs +9.3%). A two-bedroom rents for about $1,502, the median age is 46.0 and January averages -5°C.
People
Population of Sarnia
The Sarnia census agglomeration had an estimated 108,986 people on July 1, 2025, up +7.6% since 2021 (Canada grew +9.3%). The 2021 Census counted 97,592 people, +1.5% more than in 2016.
The City of Sarnia itself had an estimated 80,539 residents in 2025.
Municipalities in the Sarnia area
| Municipality | 2025 estimate | 2021 Census | 2016–21 growth | People / km² |
|---|---|---|---|---|
| Sarnia | 80,539 | 72,047 | +0.6% | 440 |
| St. Clair | 15,872 | 14,659 | +4.1% | 24 |
| Plympton-Wyoming | 9,548 | 8,308 | +6.6% | 26 |
| Point Edward | 1,989 | 1,930 | -5.3% | 585 |
| Sarnia 45 | 721 | 648 | +1.4% | 52 |
Sources: Statistics Canada, Table 17-10-0148-01, Statistics Canada, Table 17-10-0155-01, Statistics Canada, Table 98-10-0003-01
2021 Census
Who lives in Sarnia
Age
Median age is 46.0 (Canada: 41.6). 24.1% of residents are 65 or older and 15.2% are under 15.
Languages
6.8% can speak both official languages. At home, 95.8% speak mostly English, 0.4% mostly French and 2.7% mostly another language.
Immigration
— of residents are immigrants (Canada: 23.0%), and — arrived between 2016 and 2021.
Education: 20.1% of 25 to 64 year olds hold a bachelor's degree or higher; 35.3% have a college or CEGEP diploma and 9.2% a trades certificate.
Sources: Statistics Canada, Table 98-10-0030-01, Statistics Canada, Table 98-10-0223-01, Statistics Canada, Table 98-10-0227-01, Statistics Canada, Table 98-10-0302-01, Statistics Canada, Table 98-10-0384-01
Money
Income and jobs in Sarnia
Half of Sarnia households made more than $83,000 in 2020 and half made less. Across Canada the median was $84,000.
Housing
Housing in Sarnia
Average rent (October 2025)
A two-bedroom apartment rented for $1,502 a month on average, +2.0% from a year earlier and +31.5% over five years.
New homes being built
Builders started 377 new homes in the Sarnia area in the 12 months to September 2026, +35.6% from the year before. That is 3.5 new homes per 1,000 residents. Source: Statistics Canada, Table 34-10-0154-01 (CMHC housing starts)
Sources: Statistics Canada, Table 98-10-0258-01, Statistics Canada, Table 98-10-0256-01, Statistics Canada, Table 98-10-0253-01, Statistics Canada, Table 34-10-0133-01, Statistics Canada, Table 34-10-0127-01
Commuting
Getting around Sarnia
Census day 2021 fell during the COVID-19 pandemic, so transit use is lower than in normal years.
Climate
Sarnia weather and climate
30-year averages (1981–2010) from the Sarnia Airport weather station, 1.6 km from the city centre.
Source: Environment and Climate Change Canada, Canadian Climate Normals 1981–2010
Out of all Canadian metro areas with data
How Sarnia ranks
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Cities near Sarnia
FAQ
Sarnia questions, answered
What is the population of Sarnia?
The Sarnia metro area had an estimated 108,986 people on July 1, 2025 (Statistics Canada). The City of Sarnia itself had about 80,539.
How much is rent in Sarnia?
In October 2025 the average rent in Sarnia was $1,235 for a one-bedroom and $1,502 for a two-bedroom apartment (CMHC Rental Market Survey).
What is the average household income in Sarnia?
The median household income in Sarnia was $83,000 before tax in 2020 ($73,000 after tax), according to the 2021 Census. The average was $102,800.
How cold does it get in Sarnia?
January averages -4.8°C, with average lows of -8.2°C. Sarnia gets about 112 cm of snow a year, and in July the average daily high is 26.4°C (1981–2010 climate normals).
Is Sarnia bilingual?
6.8% of people in Sarnia can speak both English and French; 92.8% speak English only and 0.1% French only (2021 Census).
What is the median age in Sarnia?
The median age in Sarnia was 46.0 in the 2021 Census, compared with 41.6 for Canada.
Built October 30, 2026 from the latest published official data.