| Frontenac | |
| Settlement Type: | Municipality |
| Pushpin Map: | Canada Southern Quebec |
| Pushpin Map Caption: | Location in southern Quebec |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Type2: | Region |
| Subdivision Name2: | Estrie |
| Subdivision Type3: | RCM |
| Subdivision Name3: | Le Granit |
| Established Title1: | Constituted |
| Established Date1: | January 1, 1882 |
| Leader Title: | Mayor |
| Leader Name: | Jean-Denis Cloutier |
| Leader Title1: | Federal riding |
| Leader Name1: | Mégantic—L'Érable |
| Leader Title2: | Prov. riding |
| Leader Name2: | Mégantic |
| Area Total Km2: | 244.60 |
| Area Land Km2: | 222.73 |
| Population Total: | 1650 |
| Population As Of: | 2011 |
| Population Density Km2: | 7.4 |
| Population Blank1 Title: | Pop 2006-2011 |
| Population Blank1: | 1.7% |
| Population Blank2 Title: | Dwellings |
| Population Blank2: | 885 |
| Timezone: | EST |
| Utc Offset: | −5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | −4 |
| Postal Code Type: | Postal code(s) |
| Postal Code: | G6B 2S1 |
| Area Code: | 819 |
| Blank Name: | Highways |
| Blank Info: | |
Frontenac is a municipality in Le Granit Regional County Municipality in Estrie, Quebec, Canada, on the Canada–United States border. Its population was 1,650 as of the Canada 2011 Census.
The area was settled heavily from 1870 to 1880 by colonizers from the United Kingdom and the United States. As such, it was known until 1959 as the united counties of Spaulding and Ditchfield (cantons unis de Spaulding-et-Ditchfield). The municipality was renamed in honour of Louis de Buade de Frontenac, a governor general of New France who played a significant role in the development of the colony. Today's population is predominantly French-speaking.