Actuarial Unfunded Liability
$30.17B
Very large unfunded liability · source-reported UAAL
FY2024 source-reconciled actuarial data · Public Plans Database
Illinois State Retirement Systems
Funded ratio, unfunded liability, member counts, and 23-year financial history for Illinois State Retirement Systems, sourced from the Public Plans Database (Boston College CRR) and cross-checked against actuarial valuations.
By PlainPension · · Illinois · General State Plan · Data through FY2024
- Actuarial funded ratio
- 45.8%
- Health grade
- BReported funded ratio above the portfolio average range
- Actuarial assets
- $25.53B
- Members
- 143,675
According to the Public Plans Database, compiled by the Boston College Center for Retirement Research, Illinois State Retirement Systems is one of 197 public pension plans tracked nationwide. The plan card reports source-reconciled actuarial figures through FY2024; the multi-year table includes only years whose reported ratio ties to its actuarial dollars. This site’s database copy was last loaded in July 2026. See our methodology for the full source and update cadence.
Sliding funded-ratio path
Illinois State Retirement Systems lost 20.0 points from FY2001 (65.8%) to FY2024 (45.8%) on the reconciled series.
Illinois State Retirement Systems on a sliding funded path
According to the Public Plans Database, Illinois State Retirement Systems lost 20.0 points on the reconciled series from FY2001 to FY2024, and now reports 45.8% (grade B).
- 45.8%
- Funded · #23 of 192
- B
- Health grade
- $30.17B
- Actuarial unfunded liability
- -20.0pp
- FY2001→FY2024
Total Members
143,675
active + retired + vested
1-Year Return
4.2%
Below assumed rate · net investment return
-5.7pp vs 5-yr avg
5-Year Avg Return
9.9%
Above assumed rate · annualized, net of fees
F
Composite Health Score
24/100
Illinois State Retirement Systems
Transparent derived index from public pension-plan filings, not an official rating. A 4-dimension composite (funded ratio, contribution discipline, 5-year investment return, unfunded burden), each scored against this dataset's own percentile distribution across 197 reporting plans. Not the same as the plan's headline funded-ratio grade above. See the exact dimensions, weights, and formula.
Funded Ratio F
45.8%
Actuarial assets as a share of liabilities
Contribution Discipline F
84.1%
Share of the actuarially required contribution actually paid
Investment Returns A+
9.9%
5-year annualized investment return
Unfunded Burden F
54.4%
Unfunded liability as a share of total obligations
How this score is calculated (benchmark table)
| Dimension | P10 | P25 | P50 | P75 | P90 | Weight |
|---|---|---|---|---|---|---|
| Funded ratio (higher = better) | 57.6% | 67.2% | 75.0% | 87.0% | 97.6% | 0.35 |
| Contribution discipline (ARC) (higher = better) | 88.4% | 100.0% | 100.0% | 104.1% | 122.1% | 0.25 |
| 5yr investment return (higher = better) | 6.4% | 7.5% | 8.3% | 9.1% | 9.9% | 0.20 |
| Unfunded burden (lower = better) | 2.0% | 12.7% | 25.0% | 33.1% | 42.4% | 0.20 |
Percentiles computed across all 197 plans in this database with a reported value for that metric (2026-09-09). A dimension a plan does not report drops out of its composite, and that weight redistributes across the dimensions it does report, so thin reporting never silently lowers a score relative to a fully-reported peer.
Participant Composition
Investment Policy Mix
Funded ratio, 2001 to 2024
Assets as a share of the benefits already promised, one point per reported year. Down 20.0 points across the series. This is the multi-year table's series, so its last point can be a later year than the plan card above, which reports the plan's own latest valuation.
What changed, FY2023 to FY2024
1.2 pts funded ratioIllinois State Retirement Systems's funded ratio rose 1.2 points from FY2023 to FY2024, with assets contributing +2.7 points and the accrued liability contributing -1.5.
Funded ratio
44.7% → 45.8%
Actuarial assets
$24.07B → $25.53B (+6.1%)
Accrued liability
$53.91B → $55.70B (+3.3%)
Where the 1.2-point move came from
- Assets
- +2.7 pts
- Accrued liability
- -1.5 pts
Accrued liability is the source-reported value for benefits already promised. The two contributions are the move the ratio would have made on the prior year’s liability (assets) and the remainder (liability); they sum to the total by construction. Both years shown provide source-reconciled actuarial assets and liability, so neither figure rests on a ratio published on its own. Source: Public Plans Database (Boston College CRR / NASRA), loaded July 2026. See our funding-change board for how this plan’s move compares with the rest of the dataset.
Historical Actuarial Funding
| Year | Actuarial Ratio |
|---|---|
| 2024 | 45.8% |
| 2023 | 44.7% |
| 2022 | 44.0% |
| 2021 | 41.1% |
| 2020 | 38.7% |
| 2019 | 37.8% |
| 2018 | 36.5% |
| 2017 | 35.5% |
| 2016 | 34.3% |
| 2015 | 36.2% |
| 2014 | 33.7% |
| 2013 | 34.2% |
| 2012 | 34.7% |
| 2011 | 35.5% |
| 2010 | 37.4% |
| 2009 | 43.5% |
| 2008 | 46.1% |
| 2007 | 54.2% |
| 2006 | 52.2% |
| 2005 | 54.4% |
What the Data Says About Illinois State Retirement Systems
Illinois State Retirement Systems shows a moderate-to-serious funding gap, 30 points below the 75.5% national average across tracked plans. A 5-year average investment return of 9.9% factors into the plan's overall trajectory.
For Illinois taxpayers and plan members, the $30.17B source-reported actuarial unfunded liability is the shortfall this plan must close over time.
Where this data comes from + how funding gaps get resolved
These figures come from the Public Plans Database, a collaboration between the Boston College Center for Retirement Research and NASRA that compiles them from each plan's Comprehensive Annual Financial Reports (CAFRs) and actuarial valuations. The relationship between contribution adequacy and investment performance determines whether an unfunded liability narrows or expands year over year, and the gap itself is typically closed through some combination of higher contributions, investment returns, or benefit modifications. See our methodology for how public-pension funding differs from ERISA-backed private plans, and our disclaimer below before acting on this data.
Membership
61,651
Active Members
78,189
Retirees
143,675
Total Members
Plan Details
- Plan Type
- General State
- State
- Illinois
- Market Assets
- $25.30B
Source: Public Plans Database (PPD)
Boston College CRR / NASRA
Boston College CRR / NASRA
Plans With a Similar Funded Ratio
The closest plans nationwide to Illinois State Retirement Systems's 97.2% funded ratio.
Showing 5 of 191 plans nationwide with a reported funded ratio.
Other Illinois Plans
- Chicago Municipal Employees 97.3%
- Illinois State Universities Retirement System 96.6%
- Chicago Police 92.5%
- Illinois Teachers Retirement System 83.7%
- Chicago Fire 71.6%
Read with this plan
Every figure on PlainPension is rendered directly from the Public Plans Database (Boston College Center for Retirement Research), no number is typed in by an editor. Illinois State Retirement Systems ranks #23 of 192 by funded ratio and #57 of 190 by membership. This information is for informational purposes only and does not constitute professional advice, consult a qualified professional before acting on it. See our editorial standards & corrections policy, the typed corrections pathway, the methodology behind these numbers, or report a data error. Data current as of July 2026.