Plymouth Rock Assurance Corporation submitted a rate filing in Connecticut on October 7, 2025, for its Commercial Auto program, effective January 1, 2026, for both new and renewal business. The update affects 754 policyholders with $4.2 million in written premium and introduces an overall rate increase of 18.2%, or $765,239 in additional premium.

The filing includes base rate increases averaging 6.8% and adjustments to Increased Limit Factors (ILFs), benchmarked against Progressive’s latest filing (SERFF #PRGS-134329748) to address volatility from large losses and improve rate adequacy. The company did not employ Generalized Linear Models or external models for factor selection, citing the small size of its Connecticut book—roughly 0.6% market share.

Plymouth Rock’s tiering considers CEO or partner involvement, credit score, and prior liability limits. Physical Damage coverage showed the highest indicated need at 34.7%. Light vehicles account for about 95% of the book’s exposure. The prior rate revision was a 7.5% increase, effective September 1, 2024.