Potential Options to Keep the Highway Trust Fund Solvent Through 2036
Source: Authors’ calculations based on data from Congressional Budget Office (CBO), June 2026, and sources noted in this post.
Notes: Dollars are not adjusted for inflation but we assume fuel taxes and fees increase by 2 percent each year. We assume a typical driver drives 14,000 miles a year in a car with a MPG of 23.4. The shortfall is the gap between predicted revenues and expenditures the fund would run based on CBO’s projections. CBO projects transit spending in 2036 at 98 percent of its 2027 level, not adjusted for inflation. The General Fund transfer would require less revenue to make up the shortfall because a one-time transfer into the HTF would allow it to gain additional funds through interest over time. The spending cut and general fund transfer differ because of timing. Spending cuts happen throughout the years when the fund runs out of money, and equal the cumulative shortfall. The transfer arrives in 2027 and earns interest until it is spent, so it requires a lower total amount. Cutting spending brings no new additional revenue.
