University of California Institute of Transportation Studies

This white paper reconsiders the equity of road pricing by distinguishing between fairness and affordability—two concepts that are otherwise often conflated. A fair price assigns costs in proportion to the burdens a user imposes on others; an affordable price is one that users can pay without hardship. While both are important, these are distinct objectives, and treating them as interchangeable can obscure judgments about whether pricing is morally or ethically correct. Applying this framework suggests congestion pricing is more equitable than flat VMT charges because it better aligns payments with the social costs of driving. While congestion pricing may raise affordability concerns for some users, these concerns can be addressed through targeted redistribution of toll revenues. By contrast, unpriced roads and poorly targeted charges allow drivers to impose substantial external costs on others, undermining fairness even as they appear more affordable.