Sections 505 and 505.2 of the Illinois Marriage and Dissolution of Marriage Act and 750 ILCS 46/801 determine how to properly calculate child support in unmarried cases. These child support calculations are the same that married parents must use. Being married or unmarried does not affect your obligations to provide for your children. nnChild support is based on each parent’s income and on the number of overnights the children spend with each parent. Calculating child support under Illinois child support laws is not easy, and is best done by an experienced and skilled Illinois child support attorney. Your attorney can help you determine the true amount of child support you must pay or receive in order to properly care for your children. nnYou can ask for child support to be backdated to the date of birth unless the parents were living together, or unless the father was not aware he had a child. The courts do consider prior knowledge key to when child support should begin. nnThat prevents messy support situations from arising, such as fathers learning about their child at 17 years old and getting a bill for 17 years of child support at the same time. Per 750 ILCS 42/86(e)(2),“the prior knowledge of the person obligated to pay support of the fact and circumstances of the child’s birth.”nnIn addition to child support, both parents are required by law to pay their share of child care, daycare, or babysitters based on their percentage of income. For example, if one parent makes $70,000 a year and the other makes $30,000 a year, they would likely split childcare expenses 70/30. nnWhen the court issues a child support order, both parents must abide by this order. In Illinois, the Illinois State Disbursement Unit is an agency that collects child support from one parent and distributes it to the other. They keep track of all payments made and received. This helps in case there is a dispute later down the road.