The Political RecordFederal electoral districtsNo. 35056Ontario

Markham—Stouffville

Markham—Stouffville is a federal riding in Ontario. Helena Jaczek (Liberal, first elected to the House in 2019) represents Markham—Stouffville. Helena Jaczek (Liberal) held Markham—Stouffville for the Liberals in the 2025 election by 3,760 votes (6.1 points), with 51.4% of the vote. Niran Jeyanesan (Conservative) was second with 45.3%, on a turnout of 69.2% of 89,529 electors. Member as of 2026-11-01.

Fig. 1 — Markham—Stouffville on the board, 2023 boundaries; the ridings next door as the House holds them on 2026-11-01. Open it on the board →

Who represents Markham—Stouffville

Helena Jaczek's piece from the board. Illustration after the official portrait © House of Commons.

Helena Jaczek

Member of Parliament for Markham—Stouffville

Liberal

MP since 2019-10-21 · 3 terms

Health committee

15 speeches in the 45th Parliament, most often on Adam's Ride to Recovery.

Contact and office · House of Commons →

The 2025 result: Liberal hold

Share of the valid votes by candidate, Markham—Stouffville, April 28, 2025

Shares of the 61,644 valid votes; a candidate under 1% is counted with the others. Source: Elections Canada, official voting results, the 2025 general election.

The figures

Candidate	Party	Votes	Share
Helena Jaczek	Liberal	31,658	51.4%
Niran Jeyanesan	Conservative	27,898	45.3%
Serena Cheung	New Democratic	1,121	1.8%
Others (3)		967	1.6%

Helena Jaczek (Liberal) won Markham—Stouffville on April 28, 2025 with 31,658 votes, 51.4% of the 61,644 valid votes. Niran Jeyanesan (Conservative) was second with 27,898 (45.3%), 3,760 votes and 6.1 points behind.

Of the 61,644 valid votes, Helena Jaczek (Liberal) took 51.4%, Niran Jeyanesan (Conservative) 45.3% and Serena Cheung (New Democratic) 1.8%; the 3 other candidates took 1.6% together. Turnout was 69.2% of 89,529 electors: 61,978 ballots cast, 61,644 of them valid, for 6 candidates.

Since 2021

Against the 2021 result on these boundaries, the Liberals are up 0.3 (51.1% to 51.4%), the Conservatives up 10.8 (34.5% to 45.3%) and the New Democrats down 6.9 (8.7% to 1.8%), in points of the valid votes.

2021 is Elections Canada's transposition of that election onto the 2023 boundaries, not an election held on these lines.

Since 2004: usually Liberal

The party first in Markham—Stouffville at each general election, 2004 to 2025, on today's boundaries

2004Liberal52.6%by 19.7 points over the Conservatives
2006Liberal47.9%by 10.1 points over the Conservatives
2008†Liberal42.3%by 0.8 points over the Conservatives
2011changed handsConservative50.2%by 21.3 points over the Liberals
2015changed handsLiberal48.7%by 5.4 points over the Conservatives
2019Liberal38.9%by 6.7 points over the Conservatives
2021Liberal51.1%by 16.7 points over the Conservatives
2025Liberal51.4%by 6.1 points over the Conservatives

Each election carried onto today's boundaries by where the riding's 2025 electors lived: our estimate to 2019, Elections Canada's transposition for 2021, the official result for 2025. Parties are counted as they ran. † The first two are within two points, so which party was first is less certain.

The figures

Year	First	Share	Second	Margin (pts)	Basis
2004	Liberal	52.6%	Conservative	19.7	carried, our estimate
2006	Liberal	47.9%	Conservative	10.1	carried, our estimate
2008†	Liberal	42.3%	Conservative	0.8	carried, our estimate
2011	Conservative	50.2%	Liberal	21.3	carried, our estimate
2015	Liberal	48.7%	Conservative	5.4	carried, our estimate
2019	Liberal	38.9%	Conservative	6.7	carried, our estimate
2021	Liberal	51.1%	Conservative	16.7	transposed by Elections Canada
2025	Liberal	51.4%	Conservative	6.1	official result

The Liberals were first here at seven of the eight general elections from 2004 to 2025; the Conservatives were first in 2011. In 2025 the Liberals took 51.4% of the vote here, 7.1 points above their average of 44.3% at the seven general elections from 2004 to 2021.

On today's boundaries the Liberals were first here in 2004 (52.6%), 2006 (47.9%), 2008 (42.3%), 2015 (48.7%), 2019 (38.9%), 2021 (51.1%) and 2025 (51.4%) and the Conservatives in 2011 (50.2%), each with the share of the valid votes shown.

A stronghold is a party first at every general election since 2004, by an average of 20 points or more over the next party; held, first at every one; usually, first at all but one. By-elections are not counted. By this rule 83 of the 343 ridings are usually one party's. The results before 2021 are carried onto today's boundaries by where the riding's 2025 electors lived: our estimate, from the older boundaries of Taylor, Lucas, Kirby and Hewitt and the results in Sevi's "Who Runs?". 2021 is Elections Canada's transposition, and 2025 the official result. In 2008 the carried top two are within two points, so which party was first is less certain.

Before 2025

2021 Liberal · Helena Jaczek, by 9,033 votes (15.5 pts)
2019 Liberal · Helena Jaczek, by 5,352 votes (8.3 pts)
2015 Liberal · Jane Philpott, by 3,851 votes (6.4 pts)

In the old Markham—Stouffville on the 2013 boundaries, the riding most of the 2025 electors in today's Markham—Stouffville lived in; Elections Canada's official results.

What kind of place Markham—Stouffville is

Population: 120,8452021 census
Area: 83km²
Density: 1,465people per km²
Electors: 89,529on the 2025 lists

Distinctions · ranked against all 343 ridings

Decided before election day
On election-day polls alone another party led; advance and special ballots decided it · one of 27 of 343

Share of households that own their home is 85.2% — about 1.2 times the median riding's 71.4%.
highestlowest15th highest of 343
Median total household income is $117,000 — about 1.4 times the median riding's $84,000.
highestlowest25th highest of 343
Share who are immigrants is 46.0% — about 2.7 times the median riding's 17.3%.
highestlowest41st highest of 343
Share with French as a mother tongue is 0.7% — about 44 percent of the median riding's 1.6%.
highestlowest48th lowest of 343
Share aged 25-64 with a bachelor's degree or higher is 47.4% — about 1.7 times the median riding's 28.2%.
highestlowest57th highest of 343
Median age is 40.0 — a little lower than the median riding's 41.6.
highestlowest116th lowest of 343

2021 Census on the 2023 boundaries; each rule places this riding among all 343. Density is the census population over the riding's area.

IDid this riding change?

Yes. 92% of the 2025 electors in today's Markham—Stouffville lived in the old Markham—Stouffville; by area, 3% of the riding came from other ridings.

Share of today's electorsFormer riding

91.7%Markham—Stouffville 97.2% of the area · 27% of it kept

8.3%Markham—Unionville 2.8% of the area · 3% of it kept

How this is measured. Electors: the share of the current riding's 2025 ordinary-list electors who lived in each former riding, each 2025 polling division placed in the 2013 riding a point inside it falls in. Area: the share of the current riding's area that came from each former riding, by intersecting the 2013 and 2023 boundary files, and how much of the former riding that part was. Area is land, not population. Elections Canada counts 48 of 343 ridings as entirely unchanged.

IIThe 2025 result

Candidate	Party	Votes	%	2021	±
Helena Jaczek	Liberal	31,658	51.4%	51.1%	+0.3
Niran Jeyanesan	Conservative	27,898	45.3%	34.5%	+10.8
Serena Cheung	New Democratic	1,121	1.8%	8.7%	−6.9

3 further candidates, each under 1% of the vote

Myles O'Brien	Green	433	0.7%
René de Vries	People's	393	0.6%
Shahzad Ahmed	Other	141	0.2%

The 2021 column is Elections Canada's official transposition of the 2021 result onto these 2023 boundaries. ± is the change in each party's share. It is not "swing": with four or more competitive parties there is no single pair to swing between.

IIIHow close was it, really

Third place vs. the margin

1,121 votes

New Democratic took fewer than the 3,760-vote margin.

Election-day polls won by others

93 of 183

4 polls ended in an exact tie.

Fig. 2 — Each square is one election-day poll: ■ won by the Liberals (86) · ■ won by another party (93) · ▨ tied (4).

Flip the seatHypothetical

It would have taken 1,881 voters switching from Liberal to Conservative — 3.1% of the 61,644 valid votes, 3.0 points — to change the result. No ballot was cast this way; this only moves votes between the top two.

Voters who switch: 003,762

Liberal31,658

Conservative27,898

Still Liberal by 3,760 votes. Actual margin: 3,760.

IVElection day versus advance

Only 55.5% of this riding's votes were cast at election-day polls. The rest were advance or special ballots. On election day alone, the Conservatives led here — the seat was decided by ballots cast before the day.

On election day the Liberals took 48.0%, the Conservatives 48.1% and the New Democrats 2.0%; in advance and special ballots, 55.6%, 41.7% and 1.5%, in that order.

Share of the valid votes by party, election-day polls against advance and special ballots, Markham—Stouffville, April 28, 2025

Shares of the valid votes cast at election-day polls, and of those cast at advance polls, at mobile polls and by special ballot; the gap is the second less the first, in points. Source: Elections Canada, poll-by-poll results, the 2025 general election.

The figures

Party	Election day	Advance and special	Gap
Liberal	48.0%	55.6%	+7.6
Conservative	48.1%	41.7%	−6.4
New Democratic	2.0%	1.5%	−0.5

An association, not a cause. Voters who cast ballots before election day differed from those who turned out on the day. It does not say why. There is no poll-level turnout figure on this page: the elector count on a polling division includes people who voted in advance and were counted elsewhere.

VWhere it is

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Fig. 3 — Markham—Stouffville and its 4 neighbouring ridings.

Sources and citation

"Markham—Stouffville — federal riding profile and 2025 results."
The Political Record. https://politicalrecord.ca/riding/markham-stouffville/
Accessed 2026-11-10.

Results and transposition: Elections Canada. Boundaries: Elections Canada / Statistics Canada, Open Government Licence – Canada. Census: Statistics Canada 2021 Census. Member: House of Commons.

Figures reconcile to the certified national total of 19,641,663 votes. The member is as the House of Commons listed them on 2026-11-01. Page built 2026-11-10.