Maryland Child Support Guidelines Updates – Shared Physical Custody 2020

by | Nov 20, 2020

For child support purposes, “shared physical custody” is the minimum number of overnights a parent must have in order for the number of overnights to be included in the child support guidelines calculation.  Shared physical custody child support is typically lower than sole physical custody child support.  This is because when parents have shared physical custody it is assumed that “both parents contribute to the expense of the child or children in addition to the payment of child support.”  (Family Law Article §12-201(n)(1))

Before October 1, 2020, the minimum number of overnights to qualify for shared physical custody was 35% or 128 overnights per year.

Starting October 1, 2020 and for cases filed on or after that date, the definition of “shared physical custody” has changed to 25% or 92 overnights per year.  To view the exact language changes click here.

Also, the new law requires a mathematical adjustment to the amount of support for the lower range from 25% to 30% overnights.  Presumably, so the math makes sense to eliminate the “cliff effect”.

Why did this come about?  Because Maryland is legally required to review its child support guidelines every 4 years and because of what was known as the “cliff effect”.  The “cliff effect” meant that 1 overnight difference, between the old law’s 127 overnights (sole physical custody) and 128 overnights (shared physical custody), often made a big financial difference in the amount of monthly child support.  More money than could be justified by just 1 overnight.

The new law and mathematical adjustments soften the cliff into a slope.

What tips should parents and attorneys keep in mind?

  • The date of filing matters. If your request for child support or to modify child support was filed before October 1, 2020, the old law still applies.
  • What is the material change in your modification? Per Maryland law, changes to the child support guidelines law are not, themselves alone, a material change in circumstance to justify a modification of child support (Maryland Code, Family Law Article §12-202(b)).  Other material changes are needed to obtain a modification of child support.  Make sure those changes exist and are stated in your Court filings.  If they are not and it’s helpful to your position, point that out to the Court.
  • What if there is a big difference between support under the old law and the new? If the old law still applies to your case but the new law would result in a significantly different amount of child support, consider requesting a deviation (so, an adjustment) in the amount of support.  Family Law Article §12-202(a) allows the court to deviate from the child support guidelines (so, award a different amount) if applying the guidelines formula would be unjust or inappropriate.  If seeking a deviation, say so in your Court filings.
  • Calculate and compare! Don’t assume that a shared physical custody calculation at the lower overnight ranges will result in paying less child support than sole physical custody.  Oddly and unexpectedly, sometimes the result is more child support, not less.
  • Other expense contributions? Don’t forget about §12-201(n)(1) definition requiring contribution to expenses in addition to paying shared physical custody child support.  Lack of contributions may justify a deviation.

For other articles in this series about updates to the child support guidelines law in 2020 and 2021:

Since 2002, Lindsay Parvis has represented clients in Maryland custody, divorce, and marital matters. She negotiates, litigates, and advocates for the best interests of her clients, whether in contested litigation, uncontested settlement, or premarital and other agreements. Her clients are not only spouses and parents, but also children whose interests she is appointed by the court to represent in contested custody litigation. She is a graduate of Mount Holyoke and University of Baltimore School of Law. Lindsay strives to improve Maryland law in the General Assembly, volunteering her time to monitor, advocate, and educate about legislative developments in family law.

You can follow her for discussion, news, and developments in Maryland family law on LinkedInFacebookInstagramTwitter, and



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