Rule of 88
Age at your last birthday + years of service = 88 or more, at 55 or older. The Rule of 88 must be met in the first month of entitlement, and the member must be at least 55.
Example: 58 with 30 years = 88.
Member Handbook (2025), p. 61, Glossary (Rule of 88)Rule of 62/20
Age 62 with 20 or more years of service.
Example: 62 with 20 years.
Member Handbook (2025), p. 35, Normal Retirement Age; p. 42; p. 61, Glossary (Rule of 88, Rule of 62/20)Age 65
Any amount of service, once you're vested.
Whichever of the three comes first is your normal retirement age.
Member Handbook (2025), p. 35, Normal Retirement Age; p. 42; p. 61, Glossary (Rule of 88, Rule of 62/20)- Normal retirement age, with no reduction, is whichever of these comes first: age 65; age 62 with at least 20 years of service (Rule of 62/20); or the Rule of 88, where your age at your last birthday plus your years of service adds up to 88 or more.Member Handbook (2025), p. 35, Normal Retirement Age
- The Rule of 88 needs you to be at least 55, and it has to be met in your first month of benefits.Member Handbook (2025), p. 61, Glossary (Rule of 88)
- To start a monthly benefit you must be vested and have left all IPERS-covered employment. You must also be at least 55, or retiring on disability. Once you are 70, you can start benefits while still working.Member Handbook (2025), p. 35, Eligibility to Retire: Regular Members
- Benefits don't start on their own. They can't begin before the month IPERS receives your completed application, so apply at least 60 days before you want your first payment.Member Handbook (2025), p. 37, When to Apply for Benefits
The Rule of 88 uses your age at your last birthday. The sources don't say how IPERS counts the month your birthday falls in.
We count you as your new age for the whole month your birthday falls in, the way the law counts ages 62 and 65.
What would settle it: IPERS confirmation or an estimate for a member who reaches 88 in the month of a mid-month birthday.
The early-retirement cut
For service through June 30, 2012, the reduction is 3% for each year (0.25% for each month) you receive benefits before your closest normal retirement age. For service from July 1, 2012, it is 6% a year (0.50% a month) before your 65th birthday. No reduction applies once you reach normal retirement age. Member Handbook (2025), p. 35, Early Retirement; p. 42, Early-Retirement Reduction
Each portion of the benefit is reduced separately. The handbook example splits the multiplier by service before and after July 1, 2012 (17 years -> 34%, 9.5 years -> 19%). Member Handbook (2025), p. 43, Example 1 (Steve)
IPERS's example: Steve
Steve is 61, with 26.5 years of service (17 of them before July 1, 2012) and a $54,000 average salary. He has more than 20 years, so for his pre-2012 service his closest normal retirement age is 62, one year away. His later service is cut to 65, four years away.
| Service | Multiplier | Cut | A year |
|---|---|---|---|
| Before July 1, 201217 years · 12 months × 0.25% | 34% | 3%−$550.80 | $17,809.20 |
| From July 1, 20129.5 years · 48 months × 0.5% | 19% | 24%−$2,462.40 | $7,797.60 |
| Steve's benefit | 53% | $25,606.80 |
IPERS shows $17,809.20 + $7,797.60 = $25,606.80 a year; our calculator gives $25,606.80. IPERS doesn't give Steve's birth month; we use December, which makes its "one year" and "four years" exact. Member Handbook (2025), p. 43, Example 1: Retirement Benefits Payable BEFORE Normal Retirement Age
Iowa Code says to measure the pre-July 2012 cut using your age on your retirement date "and years of service as of June 30, 2012". IPERS's handbook example uses Steve's service when he retires: he had only 17 years in 2012, but IPERS counts to 62 "because Steve has more than 20 years of service". With his 2012 service, Iowa law would count to 65: a 12% cut on that part instead of 3%. IPERS's own rules match the handbook.
We follow the handbook, as in the Steve example.
Iowa Code §97B.50(1)(b)(1); Member Handbook (2025), p. 43, Example 1; Iowa Admin. Code r. 495—12.1(2)(e)Iowa law cuts all service 6% a year before 65 for a member who wasn't vested on June 30, 2012. The handbook applies the 3%-a-year rule to all service before July 1, 2012, with no vesting condition.
We follow the handbook. The calculator adds a note if you had under 4 years before July 2012.
What would settle it: IPERS confirmation or an estimate for a member hired 2009-2012 who was not vested on June 30, 2012.
With more than 30 years, the handbook doesn't show how IPERS divides your benefit between your years before and after July 1, 2012.
We split your benefit between the two periods in proportion to your years in each (exact for 30 years or less, as in Steve's example).
What would settle it: An IPERS early-retirement estimate for a member with 30+ years retiring before normal retirement age.
One more difference: IPERS's Regular benefit calculation web page gives only the 0.5%-a-month-before-65 reduction and omits the 3% rule for pre-July 2012 service. We use the handbook's two rates. IPERS web page Regular Members' Retirement Benefit Calculation; Member Handbook (2025), p. 42
The cut at each age
Our engine on IPERS's rules, not an IPERS example: a member born in August 1970 who stops working with 20 years (8 before July 1, 2012) on a $60,000 average salary, and starts benefits in the month of each birthday. With 20 years, 62 is the closest normal retirement age.
| Start at | Pre-2012 cut | Later cut | Monthly |
|---|---|---|---|
| 55 | −21% | −60% | $1,112−44.4% overall |
| 56 | −18% | −54% | $1,208−39.6% overall |
| 57 | −15% | −48% | $1,304−34.8% overall |
| 58 | −12% | −42% | $1,400−30% overall |
| 59 | −9% | −36% | $1,496−25.2% overall |
| 60 | −6% | −30% | $1,592−20.4% overall |
| 61 | −3% | −24% | $1,688−15.6% overall |
| 62full benefit | none | none | $2,000 |
| 63full benefit | none | none | $2,000 |
| 64full benefit | none | none | $2,000 |
| 65full benefit | none | none | $2,000 |
If you become disabled
Members retiring because of a disability (receiving Social Security or Railroad Retirement disability benefits) are not reduced for early retirement. Member Handbook (2025), p. 35; p. 60, Glossary (Disability Benefits); Iowa Code §97B.50(2)
Waiting instead of retiring early
If you're vested, you can leave your job, wait, and start benefits later with a smaller cut or none. Benefits don't start on their own: IPERS needs your application first. Member Handbook (2025), p. 37, When to Apply for Benefits
See your own dates in the calculator, or what one more year adds.
Common questions
What is IPERS's Rule of 88?
You can start a full benefit when your age at your last birthday plus your years of service equal 88 or more, as long as you're at least 55. It has to be met in your first month of benefits.
What is the Rule of 62/20?
With 20 or more years of service, you can start a full benefit at 62.
How much does IPERS reduce early retirement?
3% a year (0.25% a month) for service before July 1, 2012, counted to your closest normal retirement date; 6% a year (0.5% a month) for later service, counted to 65. The cut is permanent.
What's the earliest I can retire from IPERS?
Age 55, once you're vested and have left all IPERS-covered jobs, or at any age on disability.
Source: IPERS Member Handbook, Updated July 2025, pp. 35, 37, 42-43, 60, 61. Also: IPERS web pages; Iowa Code §§ 97B.45, 97B.50; Iowa Admin. Code r. 495—11.2, 12.1. Last reviewed .