Idaho PERSI Retirement Calculator
Estimate your Idaho PERSI Base Plan pension. Enter your age, service and 42-month average salary to see your monthly benefit, whether you meet the Rule of 90, the exact early reduction if you don't, and what the automatic COLA adds.
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How PERSI calculates your benefit
The rules here come from Idaho Code (sections 59-1342, 59-1346 and 59-1355), PERSI's Early Retirement brochure and the PERSI Member Handbook. They're for general members in the Base Plan. Police and firefighters get 2.3% and the Rule of 80.
Annual Benefit = 2% x Years of Credited Service x Average Monthly Salary x 12
The average monthly salary is your highest 42 consecutive months of gross pay. Your benefit can't be more than that average. With 30 years and a $60,000 average, you get 60%, or $36,000 a year.
When you can retire
- Service retirement at 65 with 60 months of service. Unreduced.
- Rule of 90 from 55. If your age plus credited service equals 90, unreduced. PERSI counts both in months.
- Early retirement from 55 with 60 months of service. Reduced.
The early reduction
The reduction depends on how far you are from an unreduced benefit, measured two ways. PERSI uses whichever is smaller: the years until you turn 65, or the points you're short of 90. Then it applies Idaho Code 59-1346: 0.25% a month for the first 60 months (3% a year) and 5.75% a year after that.
- 1 to 5 years early: 3%, 6%, 9%, 12%, 15%
- 6 to 10 years early: 20.75%, 26.5%, 32.25%, 38%, 43.75%
Points matter more than people expect. A 58-year-old with 30 years is 7 years from 65, which would mean 26.5%. But 58 + 30 = 88, just 2 points short of 90, so the cut is 6%. A 60-year-old with 20 years is 10 points short but only 5 years from 65, so the cut is 15%.
Each extra year of work adds two points: one for age, one for service. Two points short is one more year.
The COLA
Every March, PERSI benefits adjust for inflation. If the CPI rose at least 1%, you get 1% automatically. The board can go higher, up to the CPI or 6%, but it needs legislative approval and the fund has to be fully funded on an actuarial basis. If the CPI rises less than 1%, the adjustment matches the CPI, and your benefit can never fall below its starting amount. Your first COLA is prorated by the months you were retired that year.
At the automatic 1%, a $3,000 monthly benefit is about $3,314 after 10 years.
The Choice 401(k) Plan
PERSI also runs the Choice 401(k) Plan, a defined contribution account you can add voluntary contributions to and invest yourself. It's separate from the Base Plan pension this calculator estimates.
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Frequently asked questions
How is a PERSI pension calculated?
2% x years of credited service x your average monthly salary over your highest 42 consecutive months. With 30 years and a $60,000 average, that's 60%, or $36,000 a year. The benefit can't exceed your highest 42-month average salary.
What is the Rule of 90?
General members get an unreduced benefit before 65 if they're at least 55 and their age plus credited service equals 90, figured in years and months. A 60-year-old with 30 years qualifies. Police and firefighters use the Rule of 80 from age 50.
How much is the early retirement reduction?
3% a year (0.25% a month) for the first five years, then 5.75% a year for years six through ten, so 15% at five years early and 43.75% at ten. The years are counted to 65 or to 90 points, whichever is closer. A 58-year-old with 30 years is 7 years from 65 but only 2 points from 90, so the cut is 6%, not 21%.
Does PERSI have a COLA?
Yes. Each March, if the CPI rose at least 1%, benefits go up 1% automatically. The board can grant more, up to the CPI or 6%, but only with legislative approval and only when the fund's actuarial assets cover its liabilities. If CPI rises less than 1%, the change follows CPI, but a benefit never drops below its starting amount.
How long does it take to vest in PERSI?
60 months of credited service. A vested member who leaves gets the full benefit at 65, or earlier, from 55, once age plus service reaches 90. A reduced benefit is available from 55.