Memphrémagog (French pronunciation: [mɛmfʁemaɡɔɡ]) is a regional county municipality in the Estrie region of Quebec, Canada.

After the signing of the Treaty of Paris on September 3, 1783, the American Revolutionary War ended. the state of Vermont was established in 1791. The border of Lower Canada was then defined at approximately 45 degrees north latitude. The territory immediately adjacent to it became part of Quebec in 1848.

There are 17 subdivisions within the RCM:

Historical Census Data - Memphrémagog Regional County Municipality, Quebec

Year Pop. ±% 1991 35,984 —     1996 38,461 +6.9% 1996A 39,127 +1.7% 2001 41,871 +7.0%	Year Pop. ±% 2001A 42,267 +0.9% 2006 45,310 +7.2% 2011 48,551 +7.2% 2016 50,415 +3.8%
(A) adjusted figures due to boundary changes.

Canada Census Mother Tongue - Memphrémagog Regional County Municipality, Quebec
Census		Total		French				English				French & English				Other
Year		Responses		Count	Trend	Pop %		Count	Trend	Pop %		Count	Trend	Pop %		Count	Trend	Pop %
2021		54,300		45,080	9%	83.03%		6,870	2.9%	12.65%		1,065	86.8%	1.96%		1,080	18.02%	1.98%
2016		49,585		41,325	4.73	83.34%		6,675	6.7%	13.46%		570	2.5%	1.1%		915	22.8%	1.84%
2011		47,940		39,455	10.7%	82.30%		7,155	8.1%	14.92%		585	80.0%	1.22%		745	24.7%	1.55%
2006		44,745		35,645	10.6%	79.66%		7,785	1.0%	17.40%		325	31.6%	0.73%		990	53.5%	2.21%
2001		41,195		32,215	10.4%	78.20%		7,860	1.9%	19.08%		475	5.5%	1.15%		645	31.6%	1.57%
1996		37,830		29,175	n/a	77.12%		7,715	n/a	20.39%		450	n/a	1.19%		490	n/a	1.30%

Highways and numbered routes that run through the municipality, including external routes that start or finish at the county border:

• List of regional county municipalities and equivalent territories in Quebec
• Lake Memphremagog