The exit polls conducted during the 2021 Assembly elections in West Bengal, Tamil Nadu, Kerala, and Assam demonstrated varying levels of accuracy. In West Bengal, the exit polls significantly underestimated the Trinamool Congress's (TMC) performance, predicting a narrow win while the TMC secured 215 seats. The BJP was overestimated, with predictions suggesting a majority that did not materialize. In Tamil Nadu, while polls correctly indicated a DMK victory, they slightly overestimated the number of seats won, with the DMK and allies capturing 159 seats against predictions of 175 to 195 seats. In Kerala, the Left Democratic Front (LDF) was expected to win but the extent of their victory (99 seats) was underestimated, while the United Democratic Front (UDF) was overestimated. Conversely, exit polls for Assam were the most accurate, with predictions closely aligning with the BJP's actual win of 75 seats. Overall, the exit polls reflected a trend of overestimating opposition parties across these states.