Child Support: How is it calculated?

In Oregon, child support is calculated using the Oregon Uniform Child Support Guidelines.  Attorneys, Judges, and parents who are trying to agree on a child support figure all calculate it the same way, using the Child Support Calculator located on the Oregon Department of Justice website.  In order to run a child support calculation, you need to know (at least) five things:

  1. Each parent’s gross monthly income;
  2. Any spousal support paid to or received from a parent;
  3. The number of overnights per year each parent has with the child or children (overnights calculator here);
  4. The cost of work-related daycare and who pays it;
  5. The cost of health insurance for the parent who is insuring the child, as well as that parent’s cost for the child.

There are certainly complications, but here is a basic child support calculation based on the information below:

  1. Wilma earns $2,500 per month and Fred earns $3,500;
  2. Fred does not pay spousal support to Wilma;
  3. Wilma has Pebbles for 255 overnights per year and Fred has her for 110 overnights;
  4. Wilma pays $400 per month for Pebbles to go to daycare while Wilma and Fred are at work; and
  5. Fred pays $50 for his own health insurance, plus another $100 to insure Pebbles.

The calculation (shown here) shows Fred would presumptively pay Wilma $528 per month in child support.

Remember that this is a very basic calculation.  Child support can deviate from the Guidelines amount for any number of reasons, a list of which appears at ORS 25.280.  One common example is increasing child support above the Guidelines amount when the child has significant, recurring health care expenses.

Need more information?  Your lawyer should ask you lots of questions to identify whether a Guidelines support obligation, or a deviation, would be more appropriate for your particular set of circumstances.  The Calculator can be tricky, so if you run your own child support scenarios, consider asking your lawyer to review them for you to be sure you have run them correctly.


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