When it comes to family law, one area that often causes confusion, stress, and even heartache is paternity testing law.
Questions about who a child’s legal father is, what rights come with that, and how paternity is established can have a huge impact on custody, child support, the divorce process, and the emotional well-being of everyone involved.
If you’re navigating a divorce, separation, or even just the early stages of parenthood outside of marriage, understanding how paternity test law works can make a big difference.
Our paternity law overview breaks everything down in an approachable way, with no legal jargon overload.
What is paternity?
Simply put, paternity is the legal status of a man as the father of a child. This doesn’t always match up with biology. In some cases, the man who raises a child isn’t biologically related, but is still considered the legal father.
What is paternity law?
At its core, paternity law is the set of legal rules that determine who is considered a child’s father under the law.
Paternity law covers:
How paternity is established
The rights and responsibilities that come with being a legal father
How disputes are resolved when paternity is unclear or contested
The impact of paternity on custody, child support, and inheritance
Paternity test law in the US
Paternity test law varies from state to state, but here are some common principles:
Voluntary vs. court-ordered testing: Parents can agree to testing, or a court can order it if there’s a dispute.
Time limits: Some states limit how long after birth paternity can be challenged. Others allow challenges until the child reaches adulthood.
Consent rules: Generally, the established mother, father, or legal guardian must consent to the child being tested. If they refuse, a judge can intervene.
Married vs. unmarried parents: Married men are typically presumed to be the father, while unmarried fathers may need testing to establish legal parentage.
If you’re unsure of your state’s rules on paternity testing, a family law attorney can explain the local laws in more detail.
Why does paternity matter?
Paternity isn’t just about having a father listed on a birth certificate. It creates a legal bond between the father and the child that affects multiple aspects of life.
Here’s why it matters:
Child support
Once paternity is established, the father is legally responsible for helping to financially support the child. This ensures the child’s needs are met, even if the parents aren’t together and in the event of divorce.
Custody and visitation
Without legal paternity, a father has no automatic rights to custody or visitation. Establishing paternity is the first step for fathers who want time with their child.
You can learn more about custody in our guide to visitation.
Inheritance
Children have inheritance rights through both parents. If paternity isn’t established, a child may lose out on financial benefits like inheritance, life insurance, or Social Security survivor benefits.
Identity and emotional connection
Beyond the legal and financial side, paternity helps establish a child’s sense of identity and belonging.
Establishing paternity
If paternity isn’t presumed, it must be legally established. There are two main ways established paternity happens:
Voluntary acknowledgement
Both parents sign a form, often at the hospital when the baby is born, though this can also be done later at a government office. This adds the father’s name to the birth certificate and creates legal rights immediately.
This is the quickest way to establish paternity, but it can be difficult to undo later if either parent changes their mind on paternal rights.
Court order
If parents don’t agree, one parent can file a paternity case. The court may order genetic testing to confirm biological paternity, and once established, the court can also decide on child support, custody, and visitation rights.
What is presumed paternity?
One of the most important legal concepts in paternity law is presumed paternity. This is when the law automatically considers a man the father under certain circumstances, without requiring paternity DNA testing or a court order.
When is paternity presumed?
At birth, when married: If a child is born during a marriage, the husband is usually presumed to be the father.
During a recent divorce: If the child is born within a certain time (often 300 days) after a marriage ends, the ex-husband may still be presumed the father.
Voluntary actions: In some states, a man who acts as a father - living with the child, providing care, and publicly acknowledging the child - can be presumed to be the father.
This presumption is strong, but not absolute. It can sometimes be challenged in court with evidence like paternity tests.
What is a paternity test, and how does a paternity test work?
A paternity test is a DNA test that compares the genetic material of a child and a man to determine whether he is the biological father.
It works by collecting DNA samples - usually from a cheek swab, but sometimes using a blood sample - and analyzing them in a lab.
Each child inherits half of their DNA from their mother and half from their father, so if the child’s DNA matches the alleged father’s DNA at enough genetic markers, paternity is confirmed.
Some courts require a legal paternity test, meaning the test must be performed at an accredited facility with strict chain-of-custody rules. At-home paternity test kits are available, but these are not normally accepted in court because they lack proof that the samples weren’t tampered with.
Can you get a paternity test while pregnant?
Yes, you can get a paternity test while pregnant, though the process is a little different.
There are three main methods:
Non-invasive prenatal paternity test (NIPP)
This is the safest option, as it only requires a blood draw from the mother and a cheek swab from the alleged father.
It can be done as early as seven to eight weeks of pregnancy.
Amniocentesis
This involves collecting amniotic fluid.
It carries some risks to the pregnancy and is generally only done for medical reasons.
Chorionic villus sampling (CVS)
This involves sampling placental tissue.
Like amniocentesis, it carries risks and is usually avoided unless already being done for medical purposes.
How much is a paternity test?
The cost depends on the type of test you use and whether it needs to be legally admissible.
On average, the costs are as follows:
At-home kits: $100-$300, but these are not valid in court.
Legal paternity test: $300-$500.
Prenatal paternity test: $1,000-$2,000, depending on the method.
Some states offer reduced-cost or free paternity testing if it’s ordered by Child Support Services. If you’re going through the court system, sometimes the costs are split between the parties, or the court decides who pays.
If paternity testing is necessary as part of your divorce process, then this is an important expense to take into account when considering the overall cost of divorce.
How long does a paternity test take?
In most cases, you’ll know within a week.
Sample collection: Typically takes just a few minutes, but medical prenatal procedures will take longer.
Results: Usually received within two to five business days for standard tests, though some labs may offer rush results within 24 hours for an extra fee.
The emotional side of paternity testing
While we’ve covered the legal side, it’s worth noting the emotional impact.
The divorce process can be stressful enough for couples, but introducing paternity testing into this may stir up even more tension.
But paternity testing can also bring closure, clarity, and peace of mind.
If you’re facing this situation, remember: establishing paternity through testing isn’t just about the adults. It’s ultimately about the child’s right to know their biological heritage and have financial, medical, and emotional support.
Final thoughts
Paternity test law might sound complicated, but at its core, it’s about clarity, fairness, and protecting a child’s best interests.
Defining the legal relationship between a father and child is an important first step in determining custody and child support after divorce.
If you’re dealing with paternity issues, remember that while the process can be confusing, there are clear legal paths forward. The important thing is to focus on the child’s best interests and make decisions that give them stability, support, and a strong sense of identity.
For more guidance to help you navigate the divorce process, download the Splitup app.
