Decoding Bengal sweep: BJP retains complete haul from 2021, wrests 129 more from TMC
The Mamata Banerjee-led party, however, failed to win any seats held by other parties.
An analysis of the results shows that across all 293 seats where polling has been held, 135 seats have changed hands between the 2021 and 2026 elections. (Express Photo by Partha Paul) In its first ever Assembly election victory in West Bengal, the BJP not only managed to retain all 77 seats it had won in the 2021 polls, but it also flipped 129 seats from the Trinamool Congress (TMC), concentrated in the state’s southern districts, once known to be the Mamata Banerjee-led party’s stronghold.
An analysis of the results shows that across all 293 seats where polling has been held, 135 seats have changed hands between the 2021 and 2026 elections. While the TMC ceded 129 seats to the BJP, it also lost 2 seats each to the Congress and Humayun Kabir-led Aam Janata Unnayan (AJU) and 1 to the CPI(M). The BJP also picked up the Kalimpong seat from the Bharatiya Gorkha Prajatantrik Morcha. The TMC, however, failed to flip any seats from other parties.
While the BJP was able to retain all 77 seats it had won in 2021, the TMC only retained 80 of the 215 seats it had won five years ago. The Indian Secular Front (ISF) retained the Bhangore seat, the only one it won in 2021.
In the 77 seats retained by the BJP from 2021, the party increased its vote share in 71 seats. In these 71 seats, the BJP’s vote share rose by more than 5-percentage points in 53 seats, including in 20 seats by more than 10-percentage points. The biggest increases in vote share came in Dabgram-Phulbari (16.2-percentage points), Siliguri (15.8), and English Bazar (15.7). In the 6 seats where its vote share fell, the biggest declines came in Baharampur at 4.6-percentage points and in Darjeeling at 5.2-percentage points.

Across the 77 retained seats, the BJP recorded an average winning margin of 41,214 votes this year, up from 14,010 votes in 2021. On average, this amounts to an increased margin of 27,204 votes in each seat. Between the 2021 and 2026 polls, the BJP saw its margins rise in 72 of these 77 seats, and drop in just 5 seats.
Where TMC lost
However, the election appears to have been decided in the 129 seats flipped to the BJP from the TMC.
The TMC’s vote share dipped in all but one of these 129 seats, including by more than 10-percentage points in 42 seats. The TMC’s biggest vote share declines came in Jangipur (30.9-percentage points), Beldanga (29.1) and Karandighi (20).
The BJP seems to have capitalised on a weakening TMC, increasing its vote share in all 129 seats it flipped from the TMC, including in 64 seats by more than 10-percentage points. In the Baghmundi seat, which the BJP had left to an ally in 2021, the party secured a 49% vote share this year compared to the TMC’s 31.2%.
In 2021, the TMC had won these 129 seats by an average margin of 20,338 votes, ranging from as low as 623 in Dantan to 92,480 in Jangipur. This year, the BJP won these 129 seats by an average margin of 19,852 votes – a significant feat given that the BJP had to overcome its considerable deficits to the TMC in 2021. In Jangipur, for instance, the BJP won this time by 10,542 votes, meaning it overcame a 92,480-vote deficit to the TMC in 2021 by netting an additional 1.03 lakh votes. This time, the BJP winning margins in these 129 flipped seats ranged from 316 votes in Rajarhat New Town to 68,805 votes in Jalpaiguri.
Of the 129 seats that flipped from the TMC to the BJP, 77 are concentrated in Bengal southern districts, including North 24 Parganas, Hooghly, Paschim Medinipur, South 24 Parganas, Purba Medinipur, Howrah, Kolkata, and Jhargram. Across the state, the most flipped seat came in North 24 Parganas at 18, Purba Bardhaman at 14 and Hooghly at 12. The BJP even managed to break into districts swept by the TMC in 2021, including Howrah, Kolkata, Jhargram and Purba Bardhaman.
Among these flipped seats is Bhabanipur, where Mamata Banerjee lost to the BJP’s Suvendu Adhikari. Between 2021 and 2026, the TMC’s vote share here declined by 15.5-percentage points while the BJP’s rose by 17.8-percentage points. Mamata is among 22 TMC ministers who lost their seats to the BJP, including high-profile leaders like Chandrima Bhattacharya, Bratyabrata Basu, Sujit Bose, Aroop Biswas, Shashi Panja and Moloy Ghatak. Each of these 22 ministers saw their vote shares decline from 2021. In 2021, these ministers had won by an average margin of 30,775 votes. In 2026, they lost by an average margin of 17,824 votes.
On the TMC front, in the 80 seats it has managed to retain, the party’s vote share has declined in 67 seats, including by more than 10-percentage points in 18 seats. The TMC did see its vote share increase in 13 seats, including by more than 5-percentage points in 6 seats. The biggest vote share increase was 11.5-percentage points in Chapra, while the steepest vote share decline came in Murarai at 27-3-percentage points. In these retained seats, the TMC’s average winning margin fell from 48,628 votes in 2021 to 29,095 votes in 2026, for an average decline of 19,532 votes.