The federal gas tax has not budged from 18.4 cents per gallon since 1993, but Senator Josh Hawley wants to knock it to zero for at least three months this summer. His Gas Tax Suspension Act (S.4485), introduced in the 119th Congress after pump prices climbed this spring, would pause the federal gasoline and diesel excise taxes and, according to Hawley’s office, has already attracted interest from Democrats. If the savings sound modest, about $2 to $3 off a 15-gallon fill-up, the cost to the nation’s road-building fund is not: analysts have pegged the revenue loss at roughly $21 billion, a hole that would land squarely on a Highway Trust Fund already surviving on congressional life support.
What the bill would actually do
S.4485 directs the Treasury Department and IRS to stop collecting the 18.4-cent federal gasoline excise tax and the 24.4-cent diesel tax for a minimum of 90 days. It also suspends the small per-gallon fee that funds the Leaking Underground Storage Tank (LUST) trust fund. Once the window closes, rates snap back to current law. The bill does not alter the formulas that distribute Highway Trust Fund dollars to states, and it does not permanently repeal any tax.
Hawley framed the proposal as direct pocketbook relief. “American families are getting crushed at the pump,” he said in his announcement, pointing to national averages that have hovered above $3 a gallon for much of the past year, according to AAA’s daily fuel gauge.
How much drivers would really save
On paper, the arithmetic is straightforward: 18.4 cents multiplied by 15 gallons equals $2.76 per fill-up. In practice, gas tax holidays rarely deliver the full cut to consumers. Refiners and station owners can pocket part of the difference, particularly in markets where supply is tight and competition is thin.
The Penn Wharton Budget Model, analyzing earlier federal gas-tax holiday proposals during the 2022 price spike, estimated that roughly 72 percent of a suspension would pass through to pump prices. Applied to the current 18.4-cent rate, that translates to about 13 cents per gallon in real savings, or close to $2 on a 15-gallon tank. In areas with strong station-to-station competition and ample supply, the pass-through could climb closer to the full amount, pushing savings toward $2.76. Penn Wharton’s analysis was based on 2022 market conditions; today’s somewhat lower prices and different supply dynamics could shift the pass-through rate in either direction.
Even at the high end, the relief is small relative to total fuel costs. With the national average near $3.50 a gallon in late May 2026, the federal tax represents roughly 5 percent of what drivers pay. State gas taxes, which average about 32 cents per gallon nationwide according to the American Petroleum Institute, would remain untouched by S.4485.
The Highway Trust Fund problem
Every penny of the federal gas and diesel tax flows into the Highway Trust Fund, which bankrolls highway construction, bridge repairs, and public transit systems across all 50 states. Fuel taxes generate roughly $43 billion a year, according to House testimony on the fund’s finances. A straight 90-day pause would strip roughly $10 billion to $11 billion in dedicated revenue from the fund. The larger $21 billion figure cited in some analyses appears to account for a longer effective suspension window once pipeline lags and inventory drawdowns are included, along with the diesel-tax pause, which carries a higher per-gallon rate.
The trust fund can ill afford either number. A Congressional Research Service brief documents that Congress has transferred more than $275 billion in cumulative general-revenue infusions into the fund since 2008 to keep it solvent, as rising fuel efficiency, the growth of electric vehicles, and shifts in driving habits have steadily eroded the gas-tax base. The 2021 Bipartisan Infrastructure Law injected additional federal spending into roads and transit, but that money flows through separate authorizations and does not replenish the trust fund’s core fuel-tax revenue. Pausing collections, even temporarily, would widen the structural gap and likely force lawmakers to authorize yet another general-fund backstop or accept delays in planned projects.
State transportation departments feel these shortfalls acutely. Federal highway dollars often cover 80 percent or more of a major road project’s cost. When the trust fund runs low, it does not just stall new construction. It can freeze reimbursements for work already underway, forcing states to float costs out of their own budgets or halt crews mid-project. During a 2014 trust fund scare, several states reported delaying summer construction seasons until Congress acted.
The 2022 precedent
Congress has been here before. In the summer of 2022, President Biden urged lawmakers to suspend the federal gas tax for three months as prices surged past $5 a gallon in parts of the country. The proposal never reached a Senate vote. Critics from both parties argued the consumer savings were too small to justify the infrastructure cost, and several prominent Democratic economists, including former Treasury Secretary Larry Summers, publicly opposed it.
Several states went ahead on their own. New York, Connecticut, and Maryland each temporarily suspended portions of their state-level gas taxes, creating a real-world test case. Post-suspension research showed that the share of the tax cut reaching consumers varied widely depending on local market competition and supply conditions, reinforcing the Penn Wharton findings.
Hawley’s bill arrives in a notably different price environment. Gas is cheaper now than during the 2022 spike, which cuts both ways politically: the per-fill-up savings are smaller in absolute terms and the urgency feels less acute, but supporters argue that even modest relief matters disproportionately for lower-income households that spend a larger share of their budgets on fuel and are more likely to drive older, less fuel-efficient vehicles.
Bipartisan support: real or aspirational?
Hawley’s office has described the bill as having attracted Democratic backing. But as of late May 2026, neither the GovInfo listing for S.4485 nor the Congressional Record names specific Democratic co-sponsors. Until senators go on the record, the depth of cross-party support remains an open question. A single Democratic co-sponsor would make the bill technically bipartisan; a half-dozen would signal something far more significant.
The ambiguity is worth watching because gas tax policy has historically split both parties internally. Rural-state Democrats have sometimes backed fuel-tax relief to help constituents who drive long distances with few alternatives. Infrastructure-minded Republicans, meanwhile, have resisted anything that weakens the trust fund they rely on to bring federal dollars back to their states. Where individual senators land on S.4485 will likely say as much about their state’s driving patterns and road-funding needs as about party loyalty.
Three things that will decide this bill’s fate
First, a Congressional Budget Office score. An official cost estimate would replace the imprecise $21 billion figure with a number lawmakers can argue over in committee, and it would clarify whether the bill includes any mechanism to offset lost revenue.
Second, a public co-sponsor list. Named Democratic backers would transform S.4485 from a messaging vehicle into a genuine legislative push. Without them, the bill is likely to stall in the Senate Finance Committee.
Third, a pay-for mechanism. Unless Hawley and his allies propose a way to backfill the Highway Trust Fund during the suspension, the bill will face resistance from the Senate’s infrastructure hawks in both parties, many of whom spent years negotiating the 2021 infrastructure law and are reluctant to undercut its funding foundations.
Underneath the immediate debate sits a structural question that Congress has been deferring with general-fund patches since 2008: the gas tax was designed when fuel consumption and road use moved in lockstep. That link has frayed as vehicles grow more efficient and electric cars pay nothing into the fund at all. Every proposal to cut, pause, or replace the tax forces lawmakers closer to a reckoning over how the country funds its roads going forward, and so far, they have chosen the patch every time.
