How much Parenting Time will result in a reduction in child support?

I received a question from a parent who has the child for about one-third of the time. The parent was asking about reducing child support based on the amount of parenting time spent. Child support in Massachusetts is controlled by the child support guidelines. These guidelines specifically address parenting time. According to the guidelines, the standard split of parenting time is two-thirds with the primary parent and one-third with the other. If the other non-primary parent has significantly more than one-third parenting time, then there should be a reduction. Generally, this means that the parenting time should approach a 50/50 split. Of course, the opposite argument can be made as well–if the non-primary parent doesn’t spend much time or any time with the child, then an increase in child support is warranted.