Post-SIR Rolls Redraw West Bengal Poll Map Ahead of 2026

March 1, 2026

The publication of West Bengal’s post-Special Intensive Revision (SIR) electoral rolls has significantly altered the state’s political and demographic landscape ahead of the 2026 Assembly elections. The updated voter list, released after months of hearings and scrutiny, has reduced the electorate substantially and introduced major changes across key regions.

Huge Pruning of Voter List

The SIR exercise has cut down the total electorate from 7.66 crore to just over 7.04 crore, an 8.3 per cent contraction. Alongside this, about 60.06 lakh names are now listed as ‘under adjudication’, meaning their final inclusion or exclusion will be decided in supplementary rolls.
These changes reflect the first comprehensive voter list revision in the state in years and come at a politically sensitive time, just weeks before parties begin campaigning in earnest.

Border Belts See Sharpest Churn

The most dramatic churn is visible in districts bordering Bangladesh, where citizenship and migration issues have long shaped political debates. Significant deletions were recorded in:

• North 24 Parganas: Voter base shrank by nearly 10 lakhs.

• Nadia: About 2.73 lakh names deleted.

• Malda and Murshidabad also saw large cuts, with millions of names placed under scrutiny.

• South 24 Parganas recorded over 8 lakh deletions.

These districts collectively influence more than 125 seats in the 294-member assembly, making the churn politically consequential for both the Trinamool Congress (TMC) and the Bharatiya Janata Party (BJP).

Matua Axis and Minority District Impact

The Matua community belt across North 24 Parganas, Nadia and north Bengal have faced sharp voter roll churn, with community leaders claiming high numbers of names affected. This could have a substantial impact in 40-50 seats where the Matua refugee bloc historically anchors the BJP’s core vote bank.

Similarly, minority-dominated districts such as Malda and Murshidabad saw high numbers of voters under adjudication, raising concerns about electoral representation and turnout. Analysts warn that even small shifts in these areas could tilt assembly seats where margins in past elections were narrow.

Urban and Other Regional Shifts

Urban constituencies, including parts of Kolkata, also felt the impact. North Kolkata’s seven assembly segments witnessed deletions in hundreds of thousands of names, and areas like Bhabanipur, represented by Chief Minister Mamata Banerjee, saw tens of thousands of voters dropped.

By contrast, some high-profile seats like Nandigram saw a marginal increase in registered voters, illustrating the uneven nature of the roll changes across constituencies.

Electoral Implications Ahead of Polls

Political analysts say the SIR-induced churn adds considerable uncertainty to the 2026 contest. While the BJP could leverage issues such as the Citizenship Amendment Act (CAA) to consolidate support among impacted voters, the TMC is expected to recalibrate booth-level strategies to protect its turnout advantage. With previously tight margins in many seats, these roll revisions are likely to shape both campaign narratives and ground strategies in the weeks ahead.