Shared Custody and Child Support: How Overnights Change the Amount

Why overnights change the amount

Most child support schedules estimate what parents spend on children who live in one home. When children also sleep at the other parent's home on a regular basis, that parent pays directly for food, housing and other costs during that time, and some costs are duplicated across two homes. Many states therefore lower support once the parent who would otherwise pay has the children for enough overnights a year, and some adjust it from the first night.

What matters in each state is whether there is a threshold, how time is counted and which formula applies. In two of the states we cover the guideline has no rule for parenting time at all.

Thresholds and methods by state

States with no shared custody formula

Texas. The guideline is a percentage of the paying parent's net resources, and Chapter 154 of the Family Code has no overnight threshold and no offset formula. The amount of time of possession and access is listed only among the factors a court may consider when it decides that applying the guideline would be unjust or inappropriate (Tex. Fam. Code §154.123(b)(4)).

New York. The Child Support Standards Act works from a custodial and a non-custodial parent and has no rule for shared parenting time (Family Court Act §413(1); Domestic Relations Law §240(1-b)). Time with each parent does not change the guideline amount. Among the factors that can justify a different amount are extraordinary expenses the non-custodial parent has in exercising visitation, or expenses of extended visitation that substantially reduce the custodial parent's costs, as long as the child is not on public assistance (§413(1)(f)(9)).

States where every night counts

California. The formula in Family Code §4055 includes H%, the approximate share of time the higher earner has primary physical responsibility for the children. Time enters the calculation at every level, so there is no threshold and no separate shared custody rule. When parents have different schedules for different children, H% is the average.

Colorado. Since March 1, 2026, shared physical care means each parent keeps the children for at least one overnight a year and both contribute to their expenses (C.R.S. 14-10-115(3)(h)). Each parent's overnights give a parenting time credit percentage from a table in the statute: 73 overnights give 8.87%, and 146 give 32.32%. The credit is the total basic obligation times that percentage, and it is subtracted from that parent's share; the parent who owes more pays the difference. Support can never exceed what the same parent would owe with no overnights (§14-10-115(8)(b)). Before that date, the adjustment applied only when each parent had more than 92 overnights a year.

Arizona. The guidelines use a Parenting Time Table for the parent with less time. Under 20 days a year there is no adjustment; from 20 days the percentage rises in steps, to 17.5% at 100 days, 25% at 130, 40% at 153 and 50% at 164 days or more. That percentage of the basic obligation is subtracted from that parent's share. Days are counted in 24-hour blocks; a leftover period of 12 hours or more counts as a day, 6 to 11 hours as half a day and 3 to 5 hours as a quarter day. A period of less than 3 hours may also count as a quarter day if the parent with less time pays routine expenses for the child during it, such as meals, so short visits can add up to a step in the table. Even with essentially equal time, the parent with higher income can still owe support. A revised draft guideline, dated October 21, 2026, would apply to orders entered after January 1, 2027 if adopted; this guide describes the guidelines in effect since January 1, 2022.

States with a threshold

New Jersey. The shared parenting worksheet can be used only if a parenting plan is filed or ordered, the parent of alternate residence has the child for the equivalent of two or more overnights a week over a year or more (at least 28% of the time), and that parent shows separate living accommodations for the child (Rules of Court, Appendix IX-A, paragraph 14(c)). Not every night counts toward that threshold: blocks of five or more overnights for vacations, holidays or other periodic events are excluded, and blocks of five or more that are part of a regular rotation count only at the court's discretion and if the parent shows extra housing costs for them. The yearly total of nights alone does not show that a parent qualifies. Shared parenting awards are not presumptive and remain within the court's discretion. Unless the parties agree otherwise, the final order may not be based on a shared parenting award if the primary household's weekly net income plus the award would be less than twice the federal poverty guideline for its size (for 2026, $54,640 a year for three people), or if the court finds that household could not be maintained for the child. For this test the household's income includes means-tested income such as TANF and the net income of other adults living there, and the court may impute income to the primary parent; a sole parenting award is then calculated instead (paragraph 14(d) and (e)). The poverty figures are updated every year. Below the 28% line the sole parenting worksheet allows a parenting time adjustment of up to the basic amount times the paying parent's share of overnights times 0.37, the share of costs presumed to vary with time (Appendix IX-B). That is a separate test: the parenting time adjustment is not presumptive either when the receiving parent's household income plus the adjusted award would be under 200% of the poverty guideline.

Florida. The shared formula applies when each child spends at least 20% of the overnights of the year with each parent (Fla. Stat. §61.30(11)(b)8). The court multiplies the basic obligation, without child care and health insurance, by 1.5, multiplies each parent's share by the other parent's percentage of overnights, and nets the two; child care and health insurance are then credited or debited. Below 20%, a significant amount of time is only a reason to deviate (§61.30(11)(a)10). If a parent does not regularly exercise the schedule the adjustment relied on, and the failure was not caused by the other parent, that is a substantial change of circumstances, and a modification can reach back to the date the parent first failed to exercise it (§61.30(11)(c)).

Virginia. The shared custody calculation applies when a parent has custody or visitation for more than 90 days of the year (Va. Code §20-108.2(G)(3)). The basic obligation for combined gross income is multiplied by 1.4 to give the shared support need. For each parent, that need times the other parent's custody share, plus certain health care and child care costs, is multiplied by the parent's income share, and the two results are netted. The shared amount is presumptive unless a party shows the sole custody amount is lower, in which case the lower figure applies. Two limits apply: the calculation may not create or reduce support to an amount that seriously impairs the custodial parent's ability to keep minimal adequate housing and provide basic necessities for the child, and if either parent's gross income is at or below 150% of the federal poverty level, the shared amount is not presumed correct and the court may weigh which amount is more just (§20-108.2(G)(3)(d)). A day means 24 hours, but an overnight shorter than 24 hours for the parent with fewer overnights counts as half a day for each parent (§20-108.2(G)(3)(c)), so 91 short overnights may count as 45.5 days and fall below the threshold.

Pennsylvania. If a child spends 40% or more of the annual overnights with the paying parent, a rebuttable presumption arises that the parent is entitled to a reduction (Pa.R.Civ.P. 1910.16-4(c)). The schedule already assumes the obligor has the children 30% of the time, so the formula subtracts the percentage points by which the obligor's share of overnights exceeds 30% from that parent's percentage share of the basic obligation: 10 points at 40% of overnights, 20 at 50%. With exactly equal overnights there is one more step. Only the parent with higher net income can be the obligor, and if the result would leave the receiving parent with more of the parents' combined net income than the paying parent, support must be lowered so the combined income is split equally (Pa.R.Civ.P. 1910.16-4(c)(2)). In an example in the rule, parents with net incomes of $3,000 and $2,700, two children and equal time get a preliminary amount of $566 a month, which is lowered to $150.

The same family at different schedules

As an illustration only, this table runs one family through our calculators: Parent A has $6,000 a month and Parent B $4,000, entered as each state's own income measure (gross or net), with two children. Only the number of overnights with Parent A changes, and each overnight is assumed to be a full 24-hour period that counts toward any threshold; with shorter overnights or excluded blocks the legal count of days can be lower, as explained above. 182 nights is just under half the year, so Pennsylvania's equal time step does not apply. Texas and New York are left out because the nights do not change their guideline amounts.

Monthly transfers, paid by Parent A unless the cell says otherwise; basic support only, with every other input at the calculator's default. In New Jersey the figure includes the largest parenting time adjustment the guidelines allow, which a court may not grant. Because the income figures stand for gross pay in some states and net pay in others, compare how each column moves rather than the columns with one another.

Counting the nights

Pennsylvania averages the percentages when children have different schedules, and Florida and Arizona let a court consider whether the time is actually used. Our calculators ask for overnights a year with Parent A: every other weekend is about 52, and an even split is 182 or 183.