Bottom line
Illinois TRS Tier 1 members with pre-July 1998 service can upgrade that service to the 2.2 formula, but the charge uses a specific salary-and-service formula and can be reduced by later creditable service.Key facts
- The Illinois TRS 2.2 upgrade applies to pre-July 1998 service for eligible Tier 1 members
- The base contribution is 1% of the applicable highest salary rate multiplied by pre-July 1998 service, with no more than 20 years used in the charge
- TRS provides cost reductions or refunds tied to post-July 1998 service and service beyond 34 years
Why pre-July 1998 service can use a different formula
Illinois TRS changed to a flat 2.2% formula for service earned after June 1998. Tier 1 members who have older service that was not upgraded can still have that pre-July 1998 portion calculated under the graduated formula: 1.67% for each of the first 10 years, 1.9% for the second 10, 2.1% for the third 10 and 2.3% for service beyond 30 years. The 2.2 upgrade converts the eligible earlier service to the newer flat rate.
The value of that conversion depends on how much pre-1998 service is on the record and where those years fall in the graduated formula. A member with only a few early years can have a different change than someone with decades of pre-1998 credit. Ask TRS for an estimate using the actual service history rather than applying 2.2% to every career year yourself.
How TRS calculates the base 2.2 upgrade contribution
TRS states that the contribution equals 1% multiplied by the member’s highest salary rate in the four consecutive school years immediately before, but not including, the school year in which the upgrade application is made. That result is multiplied by the number of years of creditable service earned before July 1, 1998, using no more than 20 years in the charge.
The 20-year limit is a cost-formula limit, not a statement that only 20 years of service can be upgraded. TRS describes the election as upgrading all pre-July 1998 service. Because the salary base is tied to the school year of application, the quoted amount can change as later salary years enter the four-year lookback. Use the TRS cost quote for the intended application year.
| Input | Current rule | Planning implication |
|---|---|---|
| Upgrade rate | 1% | Applied in the contribution formula |
| Salary base | Highest rate in prior 4 consecutive school years | Application year can affect cost |
| Pre-1998 service used for charge | Actual years or 20, whichever is less | Charge uses at most 20 years |
| Service converted | All eligible pre-July 1998 service | TRS confirms account-specific result |
How to verify your pre-1998 service before requesting the quote
Log in to MyTRSIL and review the Benefits Report, which includes service credit and 2.2 upgrade information for active and inactive members. Compare the posted pre-July 1998 service with your employment history and note any optional service, refunded service or pending corrections that could change the record. A cost calculation built on an incomplete service history can be misleading even when the formula itself is correct.
Then request the current 2.2 upgrade cost from TRS and confirm which salary rate and service years were used. If retirement is approaching, also ask how any outstanding upgrade balance will be handled during the retirement process. TRS lists lump-sum and eligible rollover payment methods for a 2.2 upgrade, while direct after-tax installment payments are not available for the upgrade itself.
How later service can reduce or refund upgrade cost
Illinois TRS provides two important cost-relief rules. For every three years a member teaches and earns regular service credit after July 1, 1998, the equivalent of one year of 2.2 upgrade cost can be reduced or refunded with interest. This means the amount ultimately borne by the member can differ from the original gross cost quoted when the upgrade is first established.
TRS also states that a member retiring with more than 34 years of service credit may receive a 25% reduction in upgrade costs for each year of creditable service beyond 34, up to a 100% maximum reduction, with partial years prorated. These reductions depend on the final service record. Ask TRS to show both the gross upgrade amount and any earned reduction before comparing the net cost with the benefit change.
| Later service | Current effect | Limit |
|---|---|---|
| Each 3 years of regular service after July 1, 1998 | Equivalent of 1 year of upgrade cost reduced or refunded with interest | Depends on qualifying later service |
| Service beyond 34 years at retirement | 25% reduction per year beyond 34 | Up to 100% |
| Partial year beyond 34 | Prorated reduction | TRS calculation controls |
When the graduated formula may still matter
A member who does not upgrade keeps the graduated formula for the pre-July 1998 service, while post-June 1998 service generally receives 2.2% per year. TRS also has a special rule for members who already had at least 24 years of service as of July 1, 1998: without an upgrade, later service can receive 2.2% up to 30 years and 2.3% for service over 30 years.
Because that special provision changes the no-upgrade baseline, members with long careers before 1998 should not compare the upgrade against a simplistic 1.67% assumption. Ask TRS for both retirement estimates using the record as it stands. The meaningful comparison is the actual annuity with and without the upgrade, net of the current upgrade cost and any earned reductions.
Payment options and timing near retirement
TRS permits an after-tax lump sum or an eligible tax-sheltered rollover for the 2.2 upgrade. Its payment-options chapter says direct after-tax installment payments are not available for a 2.2 upgrade, even though installments can be used for some optional service purchases and refund repayments. A member planning around cash flow should distinguish those categories before relying on a monthly payment strategy.
At retirement, any remaining 2.2 balance needs to be resolved under TRS procedures. Obtain the current statement early enough to coordinate a rollover if that is the intended payment source. Rollover eligibility depends on federal rules and the transferring plan, and TRS requires proper certification. The official retirement estimate and payment record should be reconciled before the annuity is finalized.
Before you make a decision
- Review MyTRSIL for your pre-July 1998 service and current 2.2 upgrade information.
- Confirm any refunded, optional or pending service that could change the pre-1998 total.
- Request the current TRS upgrade quote and verify the salary base used.
- Ask TRS to show any post-1998 service reductions or refunds already earned.
- Compare official retirement estimates with and without the upgrade.
- Choose an allowed payment method and resolve the balance before retirement processing is complete.
Frequently asked questions
Who can use the Illinois TRS 2.2 upgrade?
The upgrade is relevant to eligible Tier 1 members who have creditable service earned before July 1, 1998 that remains under the graduated formula. TRS can confirm whether the account has pre-1998 service available to upgrade and whether any prior payments or reductions are already recorded.
How does Illinois TRS calculate the 2.2 upgrade cost?
TRS uses 1% times the applicable highest salary rate in the four consecutive school years immediately before the application school year, multiplied by pre-July 1998 service or 20 years, whichever is less. Ask TRS for the official account-specific quote.
Does the 20-year rule mean only 20 years get upgraded?
No. TRS describes the 20-year figure as the maximum number of pre-July 1998 years used in the contribution calculation, while the upgrade applies to all eligible pre-July 1998 service. The exact service converted should be confirmed on the TRS record.
Can my Illinois TRS 2.2 upgrade cost be reduced later?
Yes. TRS provides reductions or refunds tied to regular service earned after July 1, 1998 and a separate 25% per-year reduction for service beyond 34 years at retirement, up to 100%. The final reduction depends on your credited-service record.
Can I pay an Illinois TRS 2.2 upgrade in direct installments?
TRS says direct after-tax installment payments are not available for the 2.2 upgrade. Current listed options include an after-tax lump sum and eligible tax-sheltered rollover. Confirm payment mechanics and any retirement-stage balance directly with TRS before arranging funds.
Official sources
Sources were reviewed on September 1, 2026. Rules and member records maintained by the retirement system control.
Illinois TRS — Chapter 9: Retirement BenefitsOfficial source ↗Illinois TRS — Chapter 7: Payment OptionsOfficial source ↗Illinois TRS — Accessing Your TRS Account OnlineOfficial source ↗This article provides general educational information. It is not a benefit determination or financial, tax, or legal advice. Confirm account-specific information with the retirement system.