Congestion Mitigation and Air Quality Improvement Program (CMAQ)

Program objective

Congestion Mitigation and Air Quality Improvement (CMAQ) Program funds are limited to projects and programs that reduce transportation related emissions air quality non-attainment and maintenance areas for ozone, carbon monoxide, and particulate matter, though provision is made for States without air quality issues. This Assistance Listing 20.268 created in August 2025 was included in the previous ALN 20.205, please refer to former ALN 20.205 for FY24 and FY25 financial obligations. The new Assistance Listing 20.268 will be utilized by DOT at the start of FY 2026.

As published in the SAM.gov Assistance Listing.

No open or forecasted opportunities are currently posted under this listing. Programs often post notices on an annual cycle — see recently closed opportunities below for timing.

Eligible applicants (program level)

• ✓U.S. State Government (including the District of Columbia)
• ✓Municipality or Township government (inclusive of cities, towns, boroughs (except in Alaska), and villages)
• ✓County Government (inclusive of boroughs in Alaska, parishes and other governmental entities with geographic regional control and authority)

Apportionment of Funds As under the FAST Act, the IIJA directs FHWA to apportion funding as a lump sum for each State then divide that total among apportioned programs. Each State’s CMAQ apportionment is calculated based on a ratio specified in law. [23 U.S.C. 104(b)(4)] (See “Apportionment” fact sheet for a description of this calculation) Set-asides 2% for State Planning and Research (SPR). [23 U.S.C. 505] For a State that has a nonattainment or maintenance area for fine particulate matter (PM2.5), the BIL requires that an amount equal to 25% of the amount of the State’s CMAQ apportionment attributable to the weighted population of such areas in the State must be used for projects targeting PM2.5 reductions in those PM2.5 nonattainment and maintenance areas, including for diesel replacements (in addition to retrofits), and the BIL requires States to prioritize benefits to disadvantaged communities or low-income populations living in or adjacent to such area, to the extent practicable. [§ 11115(5); 23 U.S.C. 149(k)(1)(A) and (B)] States with low population density are not subject to this set-aside under certain conditions. [23 U.S.C. 149(k)]

Program-level eligibility from SAM.gov. Each funding notice sets its own requirements.

Frequently asked questions