When it comes to a divorce or custody case, Tennessee doesn’t leave child support numbers up to chance. The state uses a detailed formula set out in the Tennessee Child Support Guidelines, built around both parents’ income and how much time each parent spends with the child.
Knowing how the formula works won’t hand you an exact number without plugging in your specific figures, but it will help you understand what to gather, what gets added on top of the base calculation, and where there’s room for a court to depart from the standard result.
Tennessee’s Income Shares Model
Like most states, Tennessee uses an income shares approach. The underlying idea is that a child should benefit from the same share of parental income they would have had if their parents lived together. The state combines both parents’ income, determines what it would reasonably cost to support the child at that income level, and then divides that responsibility between the parents based on how much each one earns.
One key difference from some other states: Tennessee’s formula runs primarily on gross income, not income after taxes.
Step One: Calculating Adjusted Gross Income
Each parent’s gross income is calculated first. This includes wages, salaries, commissions, bonuses, and overtime; self-employment and business income; pensions, retirement, and disability payments; workers’ compensation and unemployment benefits; alimony received from a different case; and investment income such as interest, dividends, rental income, or capital gains. Means-tested public assistance benefits, such as TANF or SSI, are not counted.
From there, each parent may receive a credit for other children they support, whether those children live with them or not, along with credit for any pre-existing child support order they’re already paying. Subtracting these credits produces each parent’s Adjusted Gross Income, or AGI, which is the number used in the formula.
Step Two: The Basic Child Support Obligation
Both parents’ AGI figures are combined into one number. That combined figure is matched against Tennessee’s Child Support Schedule, a table built into the state’s guidelines that sets a Basic Child Support Obligation, or BCSO, based on combined income and the number of children involved. This is the total amount the state considers necessary to support the child or children at that income level.
Step Three: Pro Rata Shares Between the Two Parents
Once the BCSO is set, it’s divided between the parents according to each one’s percentage of the combined AGI. Tennessee refers to the parent with more overnight time as the Primary Residential Parent, or PRP, and the other parent as the Alternate Residential Parent, or ARP. In most cases, the ARP’s pro rata share becomes their support obligation, paid to the PRP.
Does Parenting Time Change the Number?
Yes. Tennessee’s guidelines include a parenting time adjustment that lowers the ARP’s support obligation as their time with the child increases, generally becoming significant once the ARP has more than 92 days a year with the child. The reasoning is similar to Florida’s approach: a parent who spends substantial time with a child is also directly covering everyday costs during that time, so the guidelines account for that instead of ignoring it.
What Gets Added to the Basic Obligation?
The BCSO isn’t the final number in most cases. Tennessee’s guidelines add in the cost of the child’s health insurance premium, work-related childcare costs, and recurring uninsured medical expenses, then divide those costs between the parents based on their pro rata share of income. These add-ons are a routine part of nearly every Tennessee child support worksheet.
When Can the Guideline Amount Be Changed?
A judge can deviate from the calculated amount if applying it strictly would be unjust or inappropriate for a particular family, but the deviation has to be explained in writing and tied to specific circumstances, such as extraordinary medical costs, travel expenses tied to visitation, or a child’s special educational needs. If you already have a support order and want to modify it later, Tennessee generally requires a significant variance between your current order and what the guidelines would produce today, typically defined as a difference of at least 15%, or a smaller flat-dollar threshold for lower support amounts.
Frequently Asked Questions
Is Tennessee child support based on gross or net income?
Gross income, with specific credits and deductions applied to reach an Adjusted Gross Income figure. This is different from states that calculate support off after-tax net income.
Who is the Alternate Residential Parent?
The ARP is the parent with fewer overnights under the parenting plan. In most cases, the ARP is the one who pays support to the Primary Residential Parent.
What if a parent is unemployed on purpose to avoid paying support?
Tennessee courts can impute income to a parent who is voluntarily unemployed or underemployed, based on factors like their work history, education, and available job opportunities in their area.
Does having more parenting time always lower support?
It can reduce the obligation once a parent crosses the guidelines’ parenting time threshold, but it doesn’t eliminate support entirely unless both parents’ incomes and time are very close to equal.
How do I know if I qualify to modify an existing order?
Generally, you need a significant variance between your current order and what the guidelines would calculate today, along with a real change in circumstances such as an income change or a change in the parenting schedule.
Next Step
If you’re setting up a new parenting plan or just trying to modify an existing order, the Tennessee child support formula rewards accurate numbers. Catherine Eaton has spent more than 20 years helping Tennessee and Florida parents work through these issues, often without ever stepping into a courtroom.