Spousal maintenance guidelines become law in Illinois A new public act dramatically changes how spousal maintenance is determined for divorcing couples whose combined gross income is less than $250,000. The law, P.A. 98-0961 , which was crafted by the ISBA Family Law Section Council, creates a formula for calculating maintenance based on the gross income of the parties and the length of the marriage. Up till now, judges calculated maintenance without using a statutory formula similar to the one that applies to child support awards, instead relying on a list of factors that appear at sections 504 and 505 of the Illinois Marriage and Dissolution of Marriage Act. As a result, maintenance decisions vary widely, and lawyers have found it difficult to predict what a court will do when awarding maintenance. The new formula will change that, once a court makes the threshold decision that maintenance is appropriate in a given case. Although judges aren’t required to use the formula,