The largest infrastructure investment in American history faces an uncertain future. The Infrastructure Investment and Jobs Act (IIJA)—the $1.2 trillion law signed in 2021—is scheduled to expire in September 2026, and Congress shows few signs of alignment on how to replace it.

With just six months until the authorization lapses, lawmakers, transportation planners, and construction companies face growing uncertainty about the future of federal infrastructure funding. The stakes are enormous: highways, bridges, transit systems, and the millions of jobs that depend on them hang in the balance.

What the IIJA Accomplished

The bipartisan infrastructure law represented a once-in-a-generation investment in American transportation. Its key provisions included:

  • $110 billion for roads, bridges, and major projects
  • $66 billion for passenger and freight rail
  • $65 billion for broadband infrastructure
  • $55 billion for water infrastructure
  • $39 billion for public transit
  • $7.5 billion for electric vehicle charging stations

Four years into implementation, the law has funded thousands of projects across every state. According to the Urban Institute, the IIJA produced an overall increase in ground transportation capital investment compared with previous years, though that increase concentrated primarily in highway projects.

The Reauthorization Challenge

Crafting a successor to the IIJA won't be easy. Several factors complicate the path forward:

Budget constraints: The federal deficit has expanded significantly since 2021, and fiscal hawks in Congress are pushing to reduce spending. Finding the funding for another multi-year, trillion-dollar infrastructure package will require either revenue increases, spending cuts elsewhere, or deficit financing that some members oppose.

Political timing: The 2026 midterm elections significantly increase the likelihood of legislative paralysis. Election-year politics make controversial votes—including infrastructure funding mechanisms—particularly difficult.

Policy disagreements: Members differ sharply on priorities. Some want to focus exclusively on traditional roads and bridges. Others push for expanded transit, rail, and EV infrastructure. Climate provisions remain contentious, as does the balance between formula funding (distributed by population and road miles) and competitive grants (awarded to the best proposals).

"We're facing the most difficult surface transportation reauthorization in decades. The policy disagreements are real, the fiscal constraints are tighter, and the political environment couldn't be worse."

— Transportation Policy Analyst, Brookings Institution

What Senate Leadership Is Planning

Senator Shelley Moore Capito, the ranking member on the Environment and Public Works Committee, has indicated she expects to unveil and mark up a bipartisan highway bill in early March. The timeline is aggressive but necessary given the September expiration.

While specifics remain under wraps, early indications suggest the proposal will:

  • Maintain robust formula funding for state highway programs
  • Continue the bridge replacement and repair initiative
  • Preserve competitive grant programs, though potentially with reformed criteria
  • Address the Highway Trust Fund's structural funding shortfall

The Highway Trust Fund, which finances most federal transportation spending, has been technically insolvent for years, requiring regular transfers from general revenue. Any sustainable reauthorization must address this fundamental fiscal problem.

Inflation Has Eroded Purchasing Power

Even as Congress debates future funding, the IIJA's current investments have been partially undermined by construction cost inflation. According to the Urban Institute, high construction cost inflation has reduced the real-world effects of the law's investments.

Material costs—particularly for concrete, steel, and asphalt—rose sharply during the post-pandemic period. Labor costs in construction have also climbed as the industry competes for workers. The result: projects that would have cost $100 million in 2021 now cost $120 million or more, meaning fewer miles of highway and fewer bridges per dollar appropriated.

This reality will inform reauthorization debates. Simply appropriating the same nominal dollar amounts as the IIJA won't maintain the same level of investment in real terms. Advocates are pushing for inflation adjustments; budget hawks counter that fiscal constraints don't allow for spending increases.

The Patchwork Scenario

Many transportation analysts consider a "Patchwork Reauthorization" the most likely outcome—a series of short-term extensions rather than a comprehensive five-year bill.

Under this scenario, Congress would pass a brief continuation of current funding levels (perhaps three to six months) before the September expiration, kicking the can to a lame-duck session or the next Congress. This pattern could repeat multiple times, creating uncertainty for state transportation agencies and construction firms.

The consequences of patchwork reauthorization include:

  • Planning difficulties: States can't commit to multi-year projects without multi-year funding certainty
  • Higher costs: Short-term funding leads to inefficient contracting and higher per-project costs
  • Delayed projects: Major undertakings get pushed back as agencies wait for funding clarity
  • Reduced investment: Overall spending likely falls below what a full reauthorization would provide

Industry Stakes

The construction industry has a lot riding on the outcome. According to the Associated General Contractors of America, federal highway and transit spending supports roughly 800,000 direct jobs, with millions more in related industries.

Construction firms have staffed up and acquired equipment based on IIJA funding expectations. A significant reduction in federal infrastructure spending would force painful layoffs and equipment divestitures.

Material suppliers—cement producers, asphalt companies, steel fabricators—face similar exposure. These capital-intensive businesses require long lead times to adjust capacity; sudden demand drops can be financially devastating.

What Happens If Congress Fails

If no reauthorization or extension passes by September, federal transportation programs would face immediate disruption. New project authorizations would halt, though projects already underway would continue until their existing funding is exhausted.

The Highway Trust Fund would continue collecting gas tax revenue but couldn't distribute it without Congressional authorization. States would be forced to fund transportation needs from their own budgets or defer projects entirely.

The last time Congress allowed a surface transportation authorization to lapse—briefly, in 2015—the disruption was modest because lawmakers quickly passed an extension. A prolonged gap would be far more damaging.

The Path Forward

The next six months will be critical. Stakeholders should watch for:

  • March committee markups: The first concrete legislative text will reveal Congressional priorities and potential deal-breakers
  • Revenue proposals: How Congress proposes to fund the bill—gas tax increases, vehicle-miles-traveled fees, general fund transfers, or something else—will determine feasibility
  • Election year dynamics: As November approaches, legislative bandwidth will shrink, making earlier action essential
  • Administration position: White House priorities and veto threats will shape negotiations

American infrastructure has benefited from the largest investment in generations. Whether that investment continues—and in what form—depends on whether Congress can overcome its divisions in the months ahead. For an institution that has struggled with routine tasks, reauthorizing a trillion-dollar infrastructure program represents a significant challenge.