The 35% Shared Custody Rule in D.C. Child Support
When a child spends at least 35% of the year with each parent, the District multiplies the basic obligation by 1.5, splits it by income share, lets each parent keep the part matching his or her time, and has the parent who owes more pay the difference, capped at the sole custody amount.
When the rule applies
Where a child spends 35% or more of the time during the year with each parent, there is a presumption of shared physical custody and the support obligation is calculated with the shared formula. If the child spends less than 35% with one parent, the court presumptively uses the sole custody method (D.C. Code 16-916.01(q)).
The formula
(A) Multiply the basic child support obligation by 1.5 to get the adjusted basic obligation. (B) Divide it between the parents by their shares of combined adjusted gross income. (C) Each parent retains the part of his or her share equal to the percentage of time the child spends with that parent. (D) Subtract the retained amount from each parent’s share to get each parent’s obligation. (E) The parent who owes more pays the difference to the other. (F) Additions and deductions for health insurance, extraordinary medical expenses and child care are then made. (G) The result cannot exceed what the paying parent would pay if the other parent had sole custody.
An example
The same family as in the worked example, but the father has the children 40% of the year and add-ons are left out.
| Step | Amount |
|---|---|
| Basic obligation, $140,400 row, two children | $28,695 |
| Multiplied by 1.5 | $43,042 |
| Father’s share (64.3%) and mother’s share (35.7%) | $27,670 / $15,372 |
| Retained: father 40% of his share, mother 60% of hers | $11,068 / $9,223 |
| Each parent’s obligation | $16,602 / $6,149 |
| Father pays mother the difference | $10,453 a year |
| Per month | $871 |
With 10% of the time with the father it was $1,537 a month; at 40% the shared formula applies and the amount falls.
Rebutting the presumption
Either parent may rebut the shared custody presumption by proving that the shared method would be unjust or inappropriate because of the parents’ particular arrangements. When the 35% line is not met, either parent may rebut the sole custody presumption by proving that the sole method would be unjust or inappropriate and that the shared method would be fair. A parent who challenges either method gets written findings explaining which method the court used.
Counting the time
The statute speaks of the percentage of time the child spends with each parent during the year. The calculator takes the percentage you enter, so use the schedule the court order or agreement provides. At exactly 35% for one parent and 65% for the other, the shared formula applies.
Questions to bring to an attorney
Ask how the court will count the child’s time, whether your schedule crosses the 35% line and whether either parent could rebut the presumption. A few overnights near 35% can change the method.
Try your own schedule
Move the time slider in the District of Columbia child support calculator across 35% to see the jump from the sole custody method to the shared custody method.
Frequently asked questions
What percentage of time is shared custody for D.C. child support?
35% or more of the year with each parent creates a presumption of shared physical custody.
What is the 1.5 multiplier in D.C. child support?
In shared custody cases the basic child support obligation is multiplied by 1.5 before the parents' shares and retained amounts are calculated.
Can the shared custody amount exceed the sole custody amount in D.C.?
No. It cannot exceed what the paying parent would pay if his or her obligation were calculated on the other parent's sole custody.
Can a parent challenge the D.C. shared custody method?
Yes. A parent can rebut the presumption by proving the method would be unjust or inappropriate because of the parents' arrangements, and the court must give written findings.
Are add-ons included in D.C. shared custody support?
Additions and deductions for health insurance, extraordinary medical expenses and child care are made after the shared calculation; the calculator leaves them out of shared custody results.
Official sources
- D.C. Code 16-916.01: child support guideline
- D.C. Code 16-916.01a: schedule of basic child support obligations
- D.C. Office of the Attorney General: child support guideline calculator
A local family law attorney can review your situation — many offer a free consultation.
This is general information, not legal advice. It is based on the cited District of Columbia statutes, rules and court opinions, and every case turns on its own facts. Confirm how the law applies to your situation with a licensed District of Columbia attorney.