Updated October 21, 2026. Quick answer: For regular formula members, the Illinois SERS Tier 2 handbook reduces a pension that starts before age 67 and then adds yearly increases. The increase is the lesser of two measures the handbook defines, and it is not compounded. The handbook says the increases are not limited by the maximum benefit.
What this section covers
In the State Employees’ Retirement System of Illinois, Tier 2 Active Member Handbook, the heading “REDUCED RETIREMENT BENEFIT” is followed by “ANNUAL PENSION INCREASES”. The first reads: “with 10 years of service credit with a pension reduced 1/2 of 1% for each month under age 67.”
The statute adds a floor the handbook sentence leaves out. 40 ILCS 5/1-160(c) lets a member who “has attained age 62” and “has at least 10 years of service credit” elect the lower annuity, and 1-160(d) reduces it “by one-half of 1% for each full month that the member’s age is under age 67”. The reduced annuity therefore cannot start before 62, and only full months count.
This page covers the regular formula only. For the choice between payment options see single life versus joint and survivor pension and survivor benefit with a government pension.
Who it applies to
The handbook states its scope: “This information applies to all active State employees who first became a member of SERS or a reciprocal system after December 31, 2010.” The eligibility paragraph for the regular formula reads “To receive a pension benefit, you must have a minimum of 10 years of creditable service.” and lists retirement at “Age 67, with 10 years of creditable service”. The reduction applies to “A regular formula member”. The statute draws one more line inside the group the handbook describes: 40 ILCS 5/1-160(a) says the Section “does not apply to a person who first becomes a noncovered employee under Article 14 on or after the implementation date of the plan created under Section 1-161 for that Article, unless that person elects under subsection (b) of Section 1-161 to instead receive the benefits provided under this Section”. A noncovered employee hired after that date is under the separate 1-161 plan unless the member makes that election.
The rules, one by one
| Rule | What the handbook says |
|---|---|
| Which formula | “The regular retirement formula applies to most SERS members.” |
| Minimum service | “To receive a pension benefit, you must have a minimum of 10 years of creditable service.” |
| Full benefit age | “Age 67, with 10 years of creditable service” |
| Early retirement reduction | “with 10 years of service credit with a pension reduced 1/2 of 1% for each month under age 67.” |
| Increase for age 67 retirees | “every year on January 1, following your first full year of retirement.” |
| Increase for reduced benefit retirees | “every January 1 after you turn age 67 and have been retired at least one full year.” |
| Increases and the maximum | “These pension increases are not limited by the 75% limitation.” |
| Maximum benefit | “The maximum regular formula retirement benefit is 75% of final average compensation.” |
The figures the handbook prints
The increase rule for retirees at 67 or older is one sentence: “you will receive a non-compounded pension increase of 3% or one-half of the unadjusted percentage increase in the Consumer Price Index for the preceding year, whichever is less,”
The statute measures that increase more precisely. 40 ILCS 5/1-160(e) calculates each annual increase “at 3% or one-half the annual unadjusted percentage increase (but not less than zero) in the consumer price index-u for the 12 months ending with the September preceding each November 1, whichever is less, of the originally granted retirement annuity”. The index is CPI-U over the 12 months ending in September, the increase is never negative, and it is taken on the originally granted annuity, which is why it does not compound.
For members who retire early, the sentence is: “you will receive a non-compounded pension increase of 3% or one-half of the unadjusted percentage increase in the Consumer Price Index for the preceding calendar year, whichever is less,”
Both stand beside the maximum, which the handbook states as “75% of final average compensation.”
What to do and where to look
The handbook says “You must apply for benefits in order to receive them.” and that “Retirement packets, which includes a retirement application, forms and information regarding insurance, taxes and direct deposit are available on the website.” It adds that “Your pension will become effective on the first day of the month following withdrawal from service.”
For how pension income is taxed in Illinois, see whether Illinois taxes pensions; the wider map is in Illinois SERS retirement decisions and public pension retirement decisions.
A worked example
This is an illustration, not a handbook example. The handbook prints the reduction rule and the increase rule; the amounts below are invented inputs run through those rules.
Reduction: a member who retires 24 months before age 67 is reduced 1/2 of 1% for each of those months. 24 months x 1/2 of 1% = 12% (computed).
Increase: suppose the unadjusted Consumer Price Index increase for the preceding year is 4%. One-half of 4% is 2%, and the lesser of 3% or 2% is 2%. If the index increase were 8%, one-half is 4%, and the lesser of 3% or 4% is 3%.
These inputs are invented for the computation; the handbook sets the rule, and the real index figure comes from the plan’s own notice.
Edition
This page reads the State Employees’ Retirement System of Illinois, Tier 2 Active Member Handbook, the current file the Illinois State Employees’ Retirement System served on October 21, 2026. Check the edition and your own tier or plan on your own member account; the handbook’s text controls over this summary.
Common mistakes
- Expecting increases to compound. The handbook calls them “non-compounded pension increase” in both versions of the rule.
- Expecting increases to start at once after an early start. For a reduced benefit the handbook says “every January 1 after you turn age 67 and have been retired at least one full year.”
- Thinking increases are held under the benefit cap. The handbook says “These pension increases are not limited by the 75% limitation.”
Related: Illinois SERS retirement decisions, single life versus joint and survivor pension, survivor benefit with a government pension, whether Illinois taxes pensions, and public pension retirement decisions.
Find the right next step for your situation
About how much do you have invested? Pick the range that fits; your next step appears immediately below.
Talk to an advisor about your pension decision
For U.S. investors with $250,000 or more in investable assets. WiserAdvisor is an independent service matching you with 2 to 3 vetted advisers. Its form asks for your ZIP code and answers to a few questions; a match is not guaranteed.
Free to request, with no obligation to hire. By submitting, you consent to calls, texts and emails from WiserAdvisor and up to three advisers. Advisers pay for introductions.
Clear Money Guide may earn a referral payment for a qualifying completed form. An introduction is not a Clear Money Guide recommendation.
Opens on WiserAdvisor’s site in a new tab.
Explore advisor help with early pension timing
Price the destination before you decide. The matching service below introduces you to advisers who pay to meet you.
Before you start, what actually happens. The form is run by Kapitalwise, our advisor-matching partner. Kapitalwise sends your details to advisers who pay for the introduction, so expect calls and texts. Clear Money Guide may earn a referral payment for a qualifying submitted form, whether or not you ever hire anyone. This is free to you and there is no obligation to hire anyone.
The Kapitalwise form opens here; you stay on this page.
What happens when you press the button
It asks about nine questions: age, investable assets, location; then your name, email and phone number, and verifies the phone by text. Nothing loads and nothing reaches Kapitalwise until you press the button.
Prefer flat-fee or hourly pricing instead? Compare ranges here.
Answer againSources
- State Employees’ Retirement System of Illinois, Tier 2 Active Member Handbook: ilsrs.illinois.gov
- Related official page (not quoted): State Employees’ Retirement System of Illinois home page: ilsrs.illinois.gov
Read from the pension system handbooks linked above on October 21, 2026. General information, not tax advice. Your own facts decide the outcome, and a pension system or a qualified professional is the right place to confirm anything consequential.