The federal Highway Trust Fund's highway account remains on course to spend tens of billions of dollars more each year than it collects in dedicated excise revenue, with the Congressional Budget Office's January 2025 baseline showing a roughly $21 billion highway-account shortfall already in fiscal year 2026 before balances are projected to approach zero in fiscal year 2028.
That calendar pressure matters because Washington still relies mainly on motor-fuel taxes set in statute a generation ago, while states plan multi-year pavement and bridge programs that assume predictable federal reimbursement.
The Congressional Research Service summarized the bind in a March 2025 report: about 85 percent of the highway account's annual revenue comes from fuel taxes, Congress has not raised those rates since 1993, and the purchasing power of that revenue has eroded once inflation and better vehicle fuel economy are accounted for.
What drivers pay today
The same CRS analysis explains the familiar 18.4-cents-per-gallon sticker on gasoline as a bundle: 18.3 cents per gallon is credited to the Highway Trust Fund and split between the highway and mass-transit accounts, and a separate 0.1 cent per gallon is directed to the Leaking Underground Storage Tank trust fund.
In a published Congressional Budget Office overview of the trust fund, CBO said that of revenues credited to the fund in 2022, about 83 percent came from excise taxes on gasoline, diesel, and other motor fuels, and that receipts from the tax of 18.4 cents per gallon on gasoline and ethanol-blended fuel contributed the largest amount, nearly 60 percent of the fund's revenues, alongside diesel and other streams.
CBO's near-term cash picture
Tabled projections reproduced in CRS from CBO's January 2025 Highway Trust Fund baseline place highway-account outlays near $61.4 billion against revenue and interest near $40.4 billion in fiscal 2026, leaving a gap of about $21.0 billion that must be covered by balances or transfers under current law.
The same projection series shows the gap widening each year afterward, with the highway account balance approaching zero in fiscal 2028 alongside the mass-transit account, at which point the Congressional Budget Office warns the Department of Transportation could be forced to slow reimbursements to states absent new revenue or further general-fund transfers.
Why 2026 still feels like a crisis even if cash lasts until 2028
A Congressional Budget Office explainer on the trust fund states that the most recent surface-transportation authorization tied to the Infrastructure Investment and Jobs Act runs through fiscal 2026, so lawmakers face a reauthorization deadline even before the projected exhaustion date arrives.
Congress has papered over past shortfalls with large general-fund transfers, including $118 billion in IIJA-related deposits that CRS tallies alongside earlier post-2008 supplements, but each transfer postpones rather than resolves the structural mismatch between indexed construction costs and flat per-gallon taxes.
Options on the table
Budget analysts have long catalogued the same handful of fixes: raise or index fuel taxes, impose new road-usage charges, cut obligated spending, or continue shifting income-tax dollars into a fund that was originally meant to be user-financed.
The Joint Committee on Taxation has estimated illustrative revenue effects from fuel-tax increases, and CBO has published scenarios showing how higher rates could close cumulative shortfalls, but those remain political choices rather than automatic adjustments.
Until Congress picks a durable pay-for, state transportation departments must keep contingency plans for delayed federal aid, and motorists should expect continued debate anytime pump prices spike and temporary gas-tax holidays are floated.