Updated August 3, 2026. Quick answer: Oklahoma is stricter than its neighbours in two specific ways. There is no notary alternative — you need two witnesses. And both of them must be disinterested: not a legatee, devisee or heir at law. Separately, a directive not on the statutory form does not authorise withdrawing artificial nutrition or hydration unless it says so explicitly.
The execution box
- Who may execute: an individual of sound mind, 18 or older.
- Signature: by the declarant.
- Witnesses: two, each 18 or older, and neither may be a legatee, devisee or heir at law.
- Notary alternative: none in this subsection.
What the statute says
An individual of sound mind and eighteen (18) years of age or older may execute at any time an advance directive for health care governing the provision, withholding, or withdrawal of life-sustaining treatment. The advance directive shall be signed by the declarant and witnessed by two individuals who are eighteen (18) years of age or older who are not legatees, devisees, or heirs at law.
— 63 O.S. §63-3101.4(A)
Compare that with Texas, where only one of the two witnesses must clear a disqualification list, or South Dakota, which asks only for “two adults”. Oklahoma applies the restriction to both witnesses, and with no notary escape hatch there is no way around it.
“Legatee, devisee or heir at law” is broader than it sounds: heir at law catches anyone who would inherit under intestacy even where a will exists and names someone else. In practice that removes most close family from both witness slots — which is precisely who is usually available.
The nutrition trap for out-of-state forms
An advance directive that is not in the form set forth in subsection C of this section and that is executed in Oklahoma shall not be deemed to authorize the withholding or withdrawal of artificially administered nutrition and/or hydration unless it specifically authorizes the withholding or withdrawal of artificially administered nutrition and/or hydration.
— 63 O.S. §63-3101.4(B)
This is the provision that quietly defeats generic paperwork. A directive executed in Oklahoma that is not on the statutory form does not authorise withholding or withdrawing artificially administered nutrition or hydration unless it specifically says so. A national template that speaks generally about “life-sustaining treatment” and never names nutrition and hydration will not carry that authority here.
This is the medical instrument, not the financial one
It covers health care decisions only. It does not let anyone pay a bill, reach an account or manage property — that is a financial power of attorney, a separate document with its own execution rules. Families routinely find the gap at the worst possible moment.
Power of attorney requirements by state
What could not be verified
We have quoted section 3101.4 subsections (A) and (B) and referenced the statutory form in subsection (C), which we have not reproduced. Revocation, when a directive becomes operative, the proxy-authority provisions, the religious-belief designation and the pregnancy rules all sit in adjoining sections not covered here.
Related: Texas, where a notary is an alternative · South Dakota, where two adults suffice.
Related: advance directive requirements by state.
General information drawn from state statutes and official state or court forms, not legal advice. These instruments are governed by the law of the state where the property sits or the document is signed, and formalities differ from state to state — execution, witnessing and recording requirements are the parts that void a document when they are missed. Your own state’s current statute governs.