Responsible for the city’s airport operations, the Chicago Department of Aviation is a largely self-funded section of the budget, relying on the city’s two airport funds and on state and federal grants for its operations.
Chicago Department of Aviation Snapshot: Appropriation & Staffing Changes from 2026 Budget
Appropriations from federal grant funding through the FAA’s Airport Improvement Program are down significantly in the 2027 budget, with a -$139.2 million decrease in the federal grant fund. However, that decline is more than counterbalanced by a $161.3 million increase in state grant funding from IDOT’s Aviation Fuel Tax Program.
Two new multimillion dollar DoA appropriation accounts have been added in the 2027 proposal: $3 million for operations and maintenance reserve and $2 million for Special Capital Projects – Airlines.
The 2027 budget proposal has a $237.3 million increase in DoA’s appropriations for outside contracting (professional and technical services), a 56.6% increase over the previous year. In 2025, the most recent full budget year for which we have actual spend data, DoA spent only 82.2% of its locally-funded contractual services budget.
New budgeted positions for 2027 include three additional Aviation Security Officer positions, despite a substantial number of unfilled vacancies in that title from Jan-Sept of this year. Likewise, the proposal adds five Project Manager positions, despite nine unfilled Project Manager positions from Jan-Sept.
Historical Context
As a self-funded department, the Department of Aviation’s budget resources are less dependent on overall city revenues. Appropriations are typically closely tied to revenues from O’Hare and Midway airport operations: the higher the city’s airport revenues, the more funds are available for DoA budgets.
Multiple consecutive years of increasing revenues from airport rates and charges have seen consecutive increases in DoA’s budget as well.
From 2011-2026, DoA appropriations grew at an average rate of 7.6% annually, or 5.3% when adjusted for inflation through 2025, compared to a citywide average rate of 5.5% (inflation-adjusted 3.2%). The current proposal would increase the department’s appropriations by 6.9% from the previous year.
Chicago Department of Aviation Appropriations and Inflation-adjusted Appropriations (2025 dollars)
Values in nominal dollars.
Values in 2025 dollars. No supplied inflation factors for 2026, 2027; those years remain gaps.
City budgets do not break out “fringe” pension and benefit costs for non-grant positions by department, instead grouping them together as citywide expenses under the Finance General section of the budget. To better reflect the real cost of service for departmental operations, BGA Policy has included an estimate of pension and benefit costs for the years 2018-2026, using Department of Finance fringe memos from each relevant year. An estimated fringe cost for the 2027 proposal uses the average annual rate of increase for each of the inputs into the fringe formulae.
Based on the city’s fringe formulae, the DoA fringe cost for nongrant employees averaged 7.8% from 2018-2026, compared to a citywide average of 26.8%. (Departments with a larger proportion of their budget dedicated to non-employee costs or with a larger proportion of grant-funded employees tend to have lower fringe costs, as their pension/benefit costs are either already factored into grant funds or are a smaller percentage of the overall departmental budget.)
Chicago Department of Aviation Appropriations with Estimated Fringe Cost of Pensions and Benefits for Budgeted Non-grant Positions, 2018–2027 (proposed)
Over the past four complete budget years for which local fund actuals/encumbrances data is available, DoA spent on average 82.4% of its locally funded budget, compared to the citywide average 86.6% local fund spend.
Chicago Department of Aviation Local Fund Actuals, 2022–2025
Staffing levels at DoA have increased as the department’s dedicated revenues and appropriations increase. Aviation is the city’s fourth-largest department by budgeted headcount, following the police, fire, and water management departments.
Overall, DoA’s budgeted headcount grew at an average annual rate of 3.6% from 2011-2026, compared to a citywide average annual change of -0.1%. The current proposal would increase budgeted headcount by 1.4% from the previous year.
Chicago Department of Aviation Budgeted Workforce, 2011–2027 (proposed)
From January through September of 2026, the months for which full-time position vacancy data is currently available, DoA averaged a 14.1% vacancy rate, compared to the citywide average of 11.2%.
Chicago Department of Aviation Full-time Vacancies, Jan-Sept 2026
211 of the department’s budgeted full-time positions were persistent vacancies (defined as the number of positions within the same combination of title, subsection, section, division, department, and fund codes that remained vacant in all nine months of available data). Of those, roughly 30% were Aviation Security Officer positions, with at least 62 positions vacant in the title each month from January through September:
Chicago Department of Aviation Persistent Full-time Vacancies, Jan-Sept 2026
Overall budgeted headcount at DoA is up 33 positions or FTEs.
Setting aside title changes, promotions, and similar adjustments of positions within general job categories, the proposed 2027 budget calls for a net seven new positions in project/program administration titles, and a total of 26 other new positions added across various titles.
New budgeted positions include three additional Aviation Security Officer positions, despite a substantial number of unfilled vacancies in that title from Jan-Sept of this year. Likewise, the 2027 budget proposal adds five Project Manager positions, despite nine unfilled Project Manager positions from Jan-Sept.
Chicago Department of Aviation Net and Percent Position/FTE Changes, 2026 to 2027 (Proposed) Budgets
DoA is 56.9% locally-funded in this year’s budget proposal, up slightly from the previous year’s 55.2%. Most of DoA’s local funding comes from the O’Hare fund, with a substantially smaller portion from the Midway fund.
Chicago Department of Aviation Fund Comparison, 2026–2027
On the grants side, 2027 saw a substantial decrease in DoA’s federal grant funding through the FAA’s Airport Improvement Program more than counterbalanced by a major increase in state grant funding from IDOT’s Aviation Fuel Tax Program:
Grant
2026 Budgeted
2027 Proposed
Net Change
Percent Change
FAA Airport Improvement – Midway
160,068,000
142,066,000
-18,002,000
-11.25%
FAA Airport Improvement – O’Hare
524,530,000
403,310,000
-121,220,000
-23.11%
IDOT – Aviation Fuel Tax Program – Midway
29,777,000
122,654,000
92,877,000
311.91%
IDOT – Aviation Fuel Tax Program – O’Hare
32,154,000
100,545,000
68,391,000
212.70%
Largest Appropriations
Unlike most departments, where personnel on payroll make up the bulk of appropriations, DoA’s largest appropriation by category in the 2027 proposal is for outside contracting through the professional and technical services appropriation, followed by a substantial amount of grant funding held in reserve balance.
Chicago Department of Aviation Top 10 Largest Appropriations, 2027 proposed
In 2025, the most recent complete budget year for which local fund actuals and encumbrances data is available, DEPT spent 83.9% of its locally-funded budget.
Only 82.2% of the locally-funded contractual services budget was expended in 2025, and only 41.6% of the equipment budget, both among DoA’s largest appropriations categories every year.
Chicago Department of Aviation 2025 Actual Spend (Local Funds)
The 2027 budget proposal has a $237.3 million increase in DoA’s appropriations for outside contracting (professional and technical services), a 56.6% increase over the previous year.
Salaries and wages on payroll, maintenance of facilities, and IT hardware also saw multimillion dollar increases, as well as the addition of a new $3 million appropriation for operations and maintenance reserve and a new $2 million appropriation for Special Capital Projects – Airlines.
DoA’s largest standalone decrease in individual appropriations was in the reserve balance category, down -$149.3 million (-25.3%) from the previous year.
Chicago Department of Aviation Net and Percent Appropriation Changes, 2026 to 2027 (proposed) Budgets
Geoffrey Cubbage analyzes policy and budgets at the Better Government Association, covering state lawmakers and Chicago City Council. He joined BGA in 2022 after directing policy and economic development for Chicago’s 40th Ward.
