Sources and method
What is counted
Names left off the draft roll
The Chief Electoral Officer, Tamil Nadu, published the names left off the draft roll of 19 December 2025 for each of the 234 assembly constituencies, under three reasons: deceased, shifted or absent, and enrolled at more than one place. The constituency rows add up to the district totals and to the state total of .
The roll before the revision
No constituency table of the roll the revision started from has been published. The draft roll plus the names left off it is that roll, in all, and every "per 100" on these pages is out of it.
The final roll
The final roll of 23 February 2026, constituency by constituency and by sex, is also the Chief Electoral Officer's own table. The rise from the draft to the final roll is the names added on claims less those removed on objections, so it counts new voters as well as names put back. That is why it is called an upper bound on names restored.
The 2026 result
Winner, runner-up and margin for every seat are from the Election Commission's constituency result pages, checked against its state-wise pages. Turnout is the votes polled over the final roll of 23 February, because the result pages do not show electors and the roll the poll was held on may differ a little.
The 2021 result
Which party won each seat in 2021, and by how much, is from the Election Commission's statistical report for that election, through a published compilation of it whose seat totals equal the declared result.
Three counts against the margin
A seat is counted on the first measure when the names left off the draft exceed the 2026 margin, and on the second when the fall from the roll before the revision to the final roll exceeds it. The third leaves out the names marked dead and multiplies the rest by the seat's turnout. It is the most cautious of the three, and it still assumes every one of those voters would have chosen the runner-up, which no one can know.
Against the district
Chennai and the districts around it removed far more names than the rest of the state, and the parties did not win evenly across districts. So each seat's rate is also set against the rate of its own district, and those differences are averaged for each party's seats.
What these tables cannot show
- Whether women, the old or the young were removed more often. The Chief Electoral Officer has not published the removals by sex or age.
- Whether each removal was right. A reason on the list is what the officer wrote down, and nobody checked it.
- How anyone removed would have voted, or why the removals fell where they did.
Downloads
The constituency and district tables behind every chart are in the Downloads menu at the top of the page.