How the seat projections work

• Polls. Every province-wide poll of British Columbia published since the 2024 election, from the polling tables on Wikipedia, as used by the site’s polling averages. Results for OneBC and CentreBC are read from the same tables’ own columns for those parties.
• The 2024 results in each of the 93 ridings, from Elections BC, as shares of valid votes. The 2024 boundaries are used again in 2026, so no transposition is needed.
• Candidates for 2026, from Wikipedia’s candidate lists checked against Elections BC, so that a party is only projected to win votes where it has a candidate.
• Regional poll results (Metro Vancouver, Vancouver Island, the rest of the province) from pollsters’ own releases, entered by hand.

The province-wide figures are the site’s polling average on the date of the newest poll: a weighted average in which a poll counts less as it ages (a Gaussian kernel with a 21-day bandwidth), more with a larger sample (square root of the sample, capped at 3,000) and less when its pollster has published several polls in the same weeks. It covers the NDP, the Conservatives, the Greens, OneBC and CentreBC; other parties and independents share the remainder.

Each riding’s 2024 result is then moved toward that average. Half of the change is applied as a uniform shift in percentage points and half in proportion to each party’s 2024 share in the riding (a party below 1% moves uniformly only). Shares are kept non-negative and summing to 100, and the ridings are then adjusted together, weighted by votes, until they reproduce the provincial average to within 0.001 points. In the backtests this blend predicted riding results about as well as either form alone.

BC United, formerly the BC Liberal Party, ran no candidates in 2024 and none in 2026. Most 2024 independents were former BC United members or candidates. Where such an independent is not running again, their vote is reallocated: 30% to CentreBC where it has a candidate, and the rest as 2020 BC Liberal voters said they would vote in Research Co.’s survey of October 2024 (Conservative 63%, NDP 25%, Green 7%, other 4%). A 2024 independent who runs again keeps that vote under their 2026 label.

OneBC and CentreBC did not exist in 2024. Each enters the 2024 baseline at its polled share, distributed in proportion to the 2024 Conservative vote, and taken from the parties its voters say they previously supported (from vote-recall questions by Angus Reid, September 2026, and Research Co., August 2026): OneBC 85% from the Conservatives, 10% from the NDP, 5% from others; CentreBC 50% from the Conservatives, 37% from the NDP, 13% from the Greens. In a test on Quebec’s Conservatives, who grew from 1.8% to 12.9% between 2018 and 2022, placing a growing party’s vote where a related party was strong located it better than spreading it evenly across the province.

A party with no candidate in a riding gets no votes there, and its projected share goes to the parties that are running. Green voters without a Green candidate are divided as 2024 Green voters who have since left the party say they will vote (NDP 60%, Conservative 21%, CentreBC 13%, OneBC 3%, other 3%, the mean of three recall tables); OneBC and CentreBC voters return to the parties they came from; any other share is divided in proportion. The projection makes no adjustment for incumbency or for individual candidates.

The exception is a sitting member running as an independent in their own riding, or an independent who won or took at least 15% there in 2024. Such a candidate keeps a share of their own 2024 vote: 39% of it if they were elected under a party label, 105% if they ran as an independent. These are the medians of every such case in Canadian provincial elections on the site (ten members who left their party and ran again, and six independents who ran again); each simulation draws the ratio at random around that median. In 2026 the rule applies in one riding, Peace River North, where Jordan Kealy, elected as a Conservative with 74.4% in 2024, runs as an independent: 29.0 points are carried forward.

A province-wide shift can misplace votes between regions. Where pollsters have published regional results within the 30 days before the newest poll, each region’s difference from that poll’s own provincial figure is averaged (weighted by regional sample size and recency) and the model’s regional result is pulled toward it. The weight given to the polls grows with their regional sample and shrinks when they disagree with each other; the shifts are balanced so the provincial totals do not change. Three regions are used: Metro Vancouver, Vancouver Island, and the rest of the province. Projections without recent regional polls use the province-wide shift alone.

The projection is simulated 10,000 times. Each simulation adds three kinds of error to every riding’s projected shares: a province-wide polling error shared by all ridings, a regional error shared within each of four regions (Metro Vancouver, the Fraser Valley, Vancouver Island, and the Interior and North), and an error for each riding. Each error moves votes between parties, so shares still sum to 100, and is larger for parties near 50% than for small parties. Their sizes come from the backtests below: 4.6, 5.25 and 6.8 percentage points respectively for a party at 50%, with heavier tails than a normal distribution (Student’s t with 4 degrees of freedom), because large riding misses happen more often than a normal curve allows.

From the simulations come each party’s median share in each riding and the range that holds the middle 90% of simulations; its chance of winning each riding; its median seat total and 90% range; and the chance that it wins a majority (47 or more of the 93 seats). The chance of no majority is the share of simulations in which no party reaches 47. A riding is Solid for a party with a 95% or higher chance of winning it, Likely at 80 to 95%, Leans at 60 to 80%, and a Toss-up when no party is above 60%.

The method was run, unchanged, on 10 provincial elections from 2020 to 2025 that had published polls and the same boundaries as the election before (766 ridings): Ontario 2022 and 2025, Alberta 2023, Manitoba 2023, Nova Scotia 2024, Quebec 2022, Prince Edward Island 2023, Newfoundland and Labrador 2021 and 2025, and British Columbia 2020. Each used only the polls published before election day. The error sizes were chosen as the most accurate setting whose 90% ranges contained at least 90% of actual riding shares and seat totals, with each election’s error sizes estimated without that election.

The projection did better than assuming every riding re-elects its party in 7 of the 10 elections; it did worse in Ontario 2022 and 2025 and Newfoundland and Labrador 2021, where incumbents held seats the provincial shift said they would lose. Given the actual provincial vote instead of the polls, the projected leader won 86.6% of ridings, so most misses come from how votes translate into seats rather than from polling error. The independent-candidate rule was estimated from cases that include these elections, so its part of the test is not independent. British Columbia is polled more often than most of the test provinces, so the error sizes probably err on the wide side.

The polls are checked several times a day. A new projection is made whenever the set of polls changes: a new poll, or a correction to one already included. Each projection is dated by the end of fieldwork of its newest poll; when several are made for the same date, the last one is kept. Every projection keeps its own page, as published. The earlier projections in the series, from before projections were first published, were computed retroactively: from the polls published up to each date, but with the model and candidate list of October 2026. Their pages say so.

No projection is made after 11:59 p.m. Pacific time on 23 October 2026. The last one before then is the final projection; none is published on or after voting day. After the election the final projection is compared with the result, seat by seat and riding by riding.

• It is only as good as the polls. If polls share an error, as they did in British Columbia in 2013, the projection shares it; the simulations allow for errors of the size seen in the backtests, not larger ones.
• Candidates are not modelled beyond who is running and the one independent rule. A well-known local candidate, a retiring member or a strong local campaign can move a riding further than the provincial shift suggests.
• Where OneBC and CentreBC voters live is assumed from where the Conservatives were strong in 2024. Their share in a given riding is therefore uncertain beyond what the simulations capture.
• The transfers for parties without a candidate and for defunct parties come from small recall questions in a few surveys.
• Regional poll results are few, entered by hand, and drawn from the pollsters’ own regional definitions, which differ from the model’s.
• Turnout is not modelled separately: the polls’ vote shares are assumed to describe those who vote.

Every projection is published as JSON: a list of all projections with their headline numbers, the latest projection in full (each riding’s projected shares and chances, the polls used and the model’s settings), and one file per date under /data/api/projections/bc-2026/by-date/.