TIFIA Financing for Airports
Federal credit assistance for airport capital projects under the Bipartisan Infrastructure Law
A reference guide for airport and aviation finance professionals
Prepared by DWU AI · Reviewed by alternative AI · Human review in progress
An AI Product of DWU Consulting LLC
March 2026
DWU Consulting LLC provides specialized municipal finance consulting services to major North American airports, aviation authorities, and municipal issuers. This article is part of the DWU AI research library, a collection of reference materials for airport finance professionals.
Scope & Methodology
This article surveys the Transportation Infrastructure Finance and Innovation Act (TIFIA) credit program as applied to airport projects, with emphasis on eligibility, structure, interest rate economics, and the airport pipeline as of March 2026. The analysis draws from statutory text, federal agency guidance, published transaction documents, and credit rating analyses. All source materials are first-hand government documents or public disclosures.
Bottom Line
TIFIA credit assistance for airport projects, authorized by the Bipartisan Infrastructure Law in 2021, offers borrowing at the U.S. Treasury rate with flexible repayment terms and subordinate lien position — reducing airport financing costs without triggering additional bonds test constraints on existing senior debt. As of March 2026, the program's airport-specific authorization has expired. Approximately 37 airport projects had submitted letters of interest (LOIs) before the September 30, 2025 deadline and may advance through credit review and closing. Permanent eligibility for new projects requires Congressional action via proposed legislation (H.R. 6168).
What TIFIA Is
The Transportation Infrastructure Finance and Innovation Act (TIFIA) credit program, codified at 23 U.S.C. §§ 601–609, provides federal credit assistance—secured loans, loan guarantees, and standby lines of credit—for surface transportation projects. The program is administered by the U.S. Department of Transportation's Build America Bureau.
TIFIA loans carry a fixed interest rate equal to the U.S. Treasury rate for a comparable maturity on the date of loan execution. For projects in rural areas, borrowers pay half the Treasury rate. Borrowers may defer principal repayment for up to five years after substantial completion, and the maximum repayment term extends up to 35 years from that date. Interest does not accrue until loan proceeds are drawn, and there is no prepayment penalty.
BIL Expansion to Airports
Prior to 2021, airport projects were not eligible for TIFIA credit assistance. Section 11101 of the Bipartisan Infrastructure Law (Pub. L. 117-58), signed November 15, 2021, expanded TIFIA eligibility to include airport development projects. Under BIL, eligible airport projects include those that would be eligible for PFC funding under 49 U.S.C. § 40117(a) or for AIP funding, including:
- Terminal buildings and passenger facilities
- Airfield infrastructure (runways, taxiways, aprons)
- Airport entrance roads
- Land acquisition for airport development
- Aircraft rescue and firefighting (ARFF) facilities
- People mover / automated transit systems
The BIL airport TIFIA authority was time-limited. It applied to projects for which a letter of interest (LOI) was submitted on or before September 30, 2025.
How TIFIA Credit Assistance Works
Credit Subsidy and Federal Budget Mechanics
TIFIA is a federal credit program, not a grant program. The federal government does not give the borrower money—it lends at favorable terms. The federal budgetary cost is the "credit subsidy," which is the estimated long-term cost to the government of providing the loan (accounting for expected defaults, interest rate differentials, and other risk factors) as calculated under the Federal Credit Reform Act of 1990 (2 U.S.C. § 661 et seq.)
Because the credit subsidy cost per dollar lent is a fraction of the face value of the loan, TIFIA generates lending capacity at a ratio that has historically averaged approximately 40:1—meaning every $1 of budget authority supports approximately $40 in loan volume. The Bipartisan Infrastructure Law provided increased budget authority for TIFIA under the program's expansion, which translates to tens of billions in lending capacity across all TIFIA-eligible project types.
Maximum Loan Amount
Statutory law permits TIFIA loans up to 49% of reasonably anticipated eligible project costs (23 U.S.C. § 603(b)(2)).
From 2014 through October 2022, the Build America Bureau applied an internal policy cap limiting loans to 33% of eligible costs. In October 2022, U.S. Transportation Secretary Pete Buttigieg removed this administrative policy cap, restoring the statutory maximum of 49%. The distinction between 33% and 49% is material for airport capital planning. On a $500 million terminal project, the difference between a 33% and 49% TIFIA loan is $80 million in additional low-cost federal credit:
| Eligible Project Cost | TIFIA at 33% | TIFIA at 49% | Difference |
|---|---|---|---|
| $500 million | $165 million | $245 million | $80 million |
| $1 billion | $330 million | $490 million | $160 million |
| $2 billion | $660 million | $980 million | $320 million |
Interest Rate Advantage
TIFIA loans are priced at the U.S. Treasury rate—the risk-free rate—which is below the yield on any airport revenue bond. The spread between the Treasury rate and an airport's bond yield varies by credit quality, market conditions, and lien position, but the borrowing cost differential is the primary financial benefit of TIFIA.
For projects qualifying as rural, the rate is half the Treasury rate. Sacramento County Department of Airports (SMF), which qualified as a rural borrower, projected savings exceeding $15 million over the life of its TIFIA loan compared to conventional financing for the same project (January 2025).