How to Fill Out and File a Voluntary Paternity Acknowledgment Form (AOP)

A voluntary paternity acknowledgment form is a signed, notarized document that legally establishes a man as a child’s father without a court case. To complete and file one, both parents fill in identifying details about themselves and the child, sign before a notary (most often at the hospital in the days after birth), and submit the form to the state vital records office, which then adds the father to the birth certificate. Federal law requires every state to offer this process, and once the form takes effect it carries the same legal weight as a court order of paternity.¹ It is usually free at the hospital and takes only a few minutes to complete.

Who Can Sign

The form is built for an unmarried mother and the man she identifies as the biological father. If the mother is married, most states presume her husband is the legal father, and that presumption blocks a different man from signing unless the husband first signs a separate Denial of Paternity. When both documents are signed, they are filed together so the state can replace the presumed father with the acknowledged one.

The form also cannot override an existing court order naming someone else as the legal father. If paternity has already been adjudicated, you have to go back through the courts rather than use this form.

Both signers must act voluntarily, and before either parent signs, the state must give oral and written notice of the legal consequences, the alternatives (such as genetic testing or a court proceeding), and each parent’s resulting rights and responsibilities.¹ If either parent is a minor, that notice must also cover rights tied to age. Some states let a minor parent sign alone; others require a parent or guardian to co-sign. Check with your state vital records office if either signer is under 18.

Where to Get the Form

Federal law requires hospitals and the state agency that keeps birth records to stock the form.¹ Hospital staff typically hand it to unmarried parents in the hours after delivery along with the birth certificate worksheet, which is the easiest time to sign because the notary, the paperwork, and both parents are usually in the same room.

If you miss that window, contact your state vital records office, local health department, or child support agency. Many states also post a downloadable copy on the vital records website. Each state designs its own version of the form within federal minimum content rules, so use the form issued by the state where the child was born.²

Information You Will Need

Before you sit down with the form, gather identifying details for the child and both parents:

Child’s full legal name as it will appear on the birth certificate, date of birth, and place of birth including the hospital or facility.
Mother’s full legal name, maiden name or name before first marriage, date of birth, place of birth, current address, and Social Security number.
Father’s full legal name, date of birth, place of birth, current address, and Social Security number.

Social Security numbers are used to cross-reference the acknowledgment in federal child support databases. If either parent does not have one, some state forms tell you to enter all nines, but follow the instructions on your state’s form. Use black or blue ink, print clearly, and do not use white-out or strikethroughs to fix mistakes; the form is scanned into digital records and corrections often cause rejection. If you make an error, start a fresh copy.

Signing Before a Notary

Both parents sign in the presence of a notary public. Do not sign in advance. A pre-signed form is typically rejected because the notary has to watch you sign, verify your identity from a government-issued photo ID, and confirm that you are signing voluntarily. Hospitals are required to provide notary services as part of their paternity establishment program, and this is usually free during the hospital stay.¹

The two parents do not have to sign at the same time or before the same notary. If the father cannot be at the hospital, the mother can sign her portion there and the father can sign later before a different notary. Private notary fees are usually modest. Once both notarized signatures are on the form, it is ready to file.

Filing the Completed Form

If you complete the form at the hospital, staff will generally forward it to the state vital records agency with the rest of the birth certificate paperwork, and you do not need to mail anything yourself. If you finish it after leaving the hospital, submit it directly to the state vital records office or department of health. Send it by certified mail so you have proof of delivery.

Some states charge a small filing fee that covers updating the birth certificate to add the father’s name; others process the form at no cost. After the agency processes it, you will receive either an amended birth certificate showing the father’s information or a separate confirmation letter. Processing times vary by state and commonly run several weeks.

What Signing Means

A completed acknowledgment is treated as a legal finding of paternity.¹ Understand what that unlocks and what it obligates before either of you signs.

Benefits for the Child

Establishing legal paternity gives the child access to benefits through both parents: Social Security survivor or disability payments, eligibility for the father’s employer health insurance, veterans’ benefits if the father served in the military, and inheritance rights. Without a legal father on record, none of these are automatic.

Child Support

Once paternity is established, either parent can ask a court or child support agency to set a support order. The acknowledgment itself does not fix a dollar amount; the agency or court calculates the obligation based on both parents’ income and the child’s needs. If the noncustodial parent does not pay, the state can enforce the order through wage garnishment, tax refund interception, and credit reporting, among other tools.

Custody and Visitation

Signing does not give the father custody or visitation. It confirms the legal parent-child relationship, but the father has to petition family court separately for any custody or visitation order. Until a court rules otherwise, the mother of a child born outside of marriage typically retains sole legal custody in most states.

The 60-Day Window to Change Your Mind

Federal law lets either signer rescind the acknowledgment within 60 days of signing, or before the date of any court or administrative proceeding involving the child (such as a child support hearing), whichever comes first.¹ No reason is required and no court approval is needed within that window.

To rescind, submit a written rescission to the same vital records office that received the original form. Some states have a dedicated rescission form; others accept a notarized letter. The state will remove the father’s name from the birth certificate and revert the child’s surname to the mother’s legal name at birth if it had been changed. The 60-day clock runs from the date you signed, not the date the state processed the form, and some states charge a processing fee for the rescission.

Challenging After 60 Days

After the rescission window closes, the acknowledgment can only be undone in court, and federal law limits the grounds to three: fraud, duress, or a material mistake of fact.¹ The person challenging carries the burden of proof.

A common scenario is a father who later learns he is not the biological parent. He would file a petition in family court alleging material mistake of fact, and the court would order genetic testing of the mother, child, and alleged father. If the results prove by clear and convincing evidence that he is not the biological father, the court can vacate the paternity finding and end future child support. The order is not retroactive: any support already owed or paid stands.

Child support and other legal responsibilities stay in full effect while a challenge is pending unless the court specifically suspends them for good cause.¹ Filing does not pause your obligations, and that is where people most often get tripped up.

1
Office of the Law Revision Counsel. 42 U.S. Code 666 – Requirement of Statutorily Prescribed Procedures to Improve Effectiveness of Child Support Enforcement
2
eCFR. 45 CFR 303.5 – Establishment of Paternity