Retirement Benefits

for Tier 1 Regular Plan Members

Earning an IMRF Pension

Your IMRF pension gives you life-long income protection. You earn service credit toward a Tier 1 Regular Plan IMRF pension by:

You will continue to earn service credit if you are on IMRF Disability or on an IMRF Benefit Protection Leave.

You must have at least eight years of service credit to receive a future IMRF pension. This eight-year requirement can include reciprocal service. Once you have at least eight years of service credit, you are guaranteed an IMRF pension for life. The more service credit you earn, the larger your pension will be.

Receiving an IMRF Pension

To begin receiving an IMRF Tier 1 Regular Plan pension, you:

Although you can retire as early as age 55, age 60 is your full retirement age. Your pension may be reduced if you retire before age 60, depending upon the amount of service credit you have.

Amount Your Pension May Be Reduced
If you retire... And you have... Your pension will be reduced by...
Between age 55 and 60 At least 8 years but less than 30 years of service credit 1/4% for each month you are under age 60
Between age 55 and 60 At least 30 but less than 35 years of service credit The lesser of:
  • 1/4% for each month you are under age 60 or
  • 1/4% for each month of service credit less than 35 years
At age 55 or later At least 35 years of service credit No reduction. You will receive your full, unreduced pension
At age 60 or later At least 8 years of service credit No reduction. You will receive your full, unreduced pension

Unused, unpaid sick days converted to service credit cannot be used to meet the eight-year requirement for a Regular Tier 1 pension or 35-year requirement for an unreduced pension under age 60.

How Much Will Your Pension Be?

The amount of your pension is based on your earnings and your service credit. To calculate the amount of your pension, IMRF uses a formula that includes:

The formula to calculate a Tier I Regular Plan pension is:

Your total pension at retirement cannot exceed 75% of your final rate of earnings.

Final Rate of Earnings (FRE)

Your highest average earnings will most likely come later in your IMRF career. If this is the case, the FRE used to calculate your pension will be your highest total earnings during any 48 consecutive months within your last 10 years of IMRF service, divided by 48. Usually, this is the average of the last 48 months of service.

Alternative FRE formula: Lifetime FRE

If you have higher earnings at the beginning of your career, an alternate FRE is used. The Lifetime FRE is an average of all your earnings reported by all your IMRF employer(s) over your entire IMRF career.

When you retire, IMRF will calculate your FRE using both methods and will use the FRE that provides you with the larger pension.

Service Credit

Service credit is your total time under IMRF, stated in years and months.

Create Pension Estimates in Member Access

Use the Pension Estimator in your Member Access account to create your own pension estimates. You can customize your estimates using a variety of different situations, such as different ages at retirement, different amounts of future service credit you think you might earn, etc. 

Annual Pension Increases

Under Tier 1, your pension is increased by 3% of the original amount on January 1 every year after you retire. 

Your first annual increase is based upon the number of months you are retired in your first year. If your pension effective date is January 1, your first year increase will also be 3%. Otherwise, your first year increase will be less than 3%.

First Year Increase Calculation Example
This example uses a pension of $800.00 per month with an effective date of July 1, 2014
The full 3% annual increase on 12 months of pension payments is $24.00 $800.00 x 3% = $24
However, the pension was in effect for only 6 months in the first year of retirement (July through December), so the first annual increase is applied to only 6 months of pension payments:
6 months = 1/2 of 12 months Full increase of $24.00 x 1/2 = $12.00
The annual increase for January 1, 2015: $12.00
The annual increase for January 1, 2016, and every year after: $24.00
Annual increases are always based on the original pension amount and are not compounded

Supplemental Benefit Payment ("13th Payment")

After you have retired and have received pension payments for at least 12 months in a row, you will be eligible for a supplemental benefit payment every July. When you first retire, you must have retired on or before June 30 to receive a 13th Payment the next year. For example:

If you retire… You will receive your first 13th Payment in…
On or before June 30, 2017 July of 2018
After June 30, 2017 July of 2019

You will receive this supplemental payment with your usual July pension payment. The amount varies every year, but it will always be less than your monthly pension amount.