Teresa J. Armstrong has cast 110 recorded division votes in the current parliament, voting yea on 33 (30%) and nay on 54 (49%). Armstrong was absent for 23 votes (21% of all divisions). Armstrong voted with the winning majority 15% of the time.

In the February 2025 election, Armstrong won London—Fanshawe with 47.59% of the vote, a likely margin of +13.4% over Pete Vanderley (PC, 34.21%). Turnout in the riding was 41.27%.

Of the 110 votes, 64 were on bills and 23 were procedural motions. Opposition members typically show lower majority-alignment rates, as they vote against government bills.