Marital Share of a Pension in an Illinois Divorce
Hunt formula · reviewed September 7, 2026
Shows what share of a pension belongs to the marriage, and what the former spouse would receive from each monthly check. AboutLess
In plain words. A pension earned during a marriage is marital property, even though only one spouse's name is on it. Illinois courts usually divide it with a fraction: the years in the plan during the marriage, over all the years in the plan by retirement. That fraction of each pension check is marital, and the former spouse typically receives half of it. This tool takes the years before, during, and after the marriage, the monthly pension, and the split, and shows the former spouse's monthly share. It also shows the smaller figure that results if the pension is frozen at the divorce instead.
Why it matters. For many couples the pension is the largest asset in the divorce, and the way the fraction is written into the order decides whether raises and years of service after the divorce count. The difference between the two methods can be hundreds of dollars a month for life.
An example. Five years in the plan before the wedding, fifteen years married, ten more until retirement, and a $4,000 monthly pension: half the years are marital, so $2,000 of each check is marital and the former spouse receives $1,000 a month. Frozen at the divorce on the $2,200 earned by then, the share would be $825.
Where it stops. It counts whole years and one continuous period in the plan. It leaves out early-retirement reductions, survivor benefits, cost-of-living increases, and the plan's own rules. A public pension in Illinois is divided by a QILDRO, a private one by a QDRO, and either has to be drafted by an attorney and accepted by the plan before anything is paid. Everything it leaves out.
The monthly benefit the plan projects at retirement, in today's dollars. It is on the plan's benefit statement.
The benefit earned so far, from the same statement. Leave it blank and the tool spreads the retirement benefit evenly over the years of service.
Enter 0 if the job began after the wedding.
From the wedding, or from joining the plan if later, to the day the petition was filed.
Enter 0 if the spouse with the pension has already retired.
Half is the usual split. The judgment or the settlement sets it.
- Marital share of the pension
- 50%
- 15 of 30 years of service
- Marital portion of each check
- $2,000
- Split 50% to the former spouse, 50% to the spouse with the pension
- Former spouse's share if the pension were frozen at the divorce
- $825
- 50% of 75% of the $2,200 earned by then
The fraction is the whole method. Years of service before the wedding and after the filing belong to the spouse with the pension. The years in between belong to the marriage. Under the usual Illinois order the fraction is applied to the pension as it is actually paid at retirement. Raises and years of service after the divorce lift the marital portion in dollars even as they shrink the fraction. An order that freezes the benefit at the divorce fixes the former spouse's share at the smaller figure on the last card. A public pension in Illinois is divided by a court order called a QILDRO, and a private plan by one called a QDRO. Either is drafted by an attorney and accepted by the plan before anything is paid.
This follows the Hunt formula Illinois courts use to divide a pension earned partly during a marriage. It assumes whole years, one continuous period in the plan, a benefit stated in today's dollars, and no early-retirement reduction or survivor option. It leaves out the plan's own rules, cost-of-living increases, a lump-sum offset against other property, and the written consent a public pension member who joined before July 1999 must give. Educational, not advice.
This is a simplified model, not your actual tax return or plan. It only knows what you type in, leaves out rules that may apply to you, and cannot weigh the other facts and trade-offs a real decision depends on. Before you act, talk with a professional who knows your whole situation.
Educational only, not investment, tax, or legal advice. Results are hypothetical estimates that vary with each use and over time and are not guaranteed accurate or complete. Using this tool creates no client relationship with Considerate Capital, and the site that linked here is not affiliated with it. By using it you agree to the tool terms.