Informal vs. Formal Probate in Idaho
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By Ronald W. Brilliant, Attorney at Law · Licensed in Idaho, Nevada & California · Last reviewed: September 2026 against Idaho Code Title 15, Chapter 3
Every Idaho probate begins with a choice: open the estate informally before the registrar, or formally before a judge. Most uncontested estates use informal probate. Formal probate gives more certainty and is the forum for disputes. This page explains both, plus supervised administration and special administrators.
Side-by-Side Comparison
| Informal Probate | Formal Probate | |
|---|---|---|
| Who decides | The registrar, based on a verified application | A judge, after notice and hearing |
| Earliest timing | Will: 5 days after death; appointment: 120 hours after death | After notice and hearing |
| Notice before filing | Limited: those who demanded notice, an existing personal representative, and anyone with equal or prior right to serve | Spouse, children, heirs, devisees, named executors, and any existing personal representative |
| Finality | Conclusive until superseded by a formal order | Binding on all persons, subject to appeal and limited vacation |
| Best for | Uncontested estates with a clear will or clear heirs | Doubts about the will, expected disputes, lost wills, unknown heirs |
Informal Probate
The Application
An interested person files a verified application with the registrar stating the required facts about the decedent, the heirs and devisees, the county of domicile, and any will (§ 15-3-301). The applicant must swear that, after exercising reasonable diligence, they are unaware of any instrument revoking the will. When the entire estate is community property and there is no will, a surviving spouse can apply for an informal statement that the spouse is the sole heir.
What the Registrar Checks
Before informally probating a will, the registrar must be satisfied that the application is complete, the applicant swore to it, the applicant is an interested person, venue is proper, an original, apparently unrevoked will is in the registrar’s possession, and the time limits are met (§ 15-3-303). A will that appears properly executed is probated if at least 5 days have passed since death (§ 15-3-302). The registrar makes similar findings before informally appointing a personal representative, which can occur no sooner than 120 hours after death, or 30 days if the decedent was a nonresident unless the decedent’s home-state representative applies (§§ 15-3-307, 15-3-308).
When Informal Probate Is Not Available
- The registrar must decline informal probate of a will that is part of a known series of wills (other than a will and its codicils) when the latest does not expressly revoke the earlier ones (§ 15-3-304).
- The application must be denied if a personal representative has already been appointed in another Idaho county, or if a will of the decedent has already been the subject of a probate order, except for a will probated in another state, which can be probated here on an authenticated copy (§ 15-3-303(b), (d)).
- Informal appointment must be declined if there may be an unrevoked will affecting Idaho property that has not been filed for probate (§ 15-3-311).
- A declined application is not a final decision: the matter can proceed by formal petition (§§ 15-3-305, 15-3-309).
Notice in Informal Proceedings
Before filing, notice is required only to anyone who has filed a demand for notice and to any existing personal representative (§ 15-3-306). For appointment, notice also goes to anyone with an equal or higher right to serve who has not waived it (§ 15-3-310). After a will is informally probated without letters being issued, or a determination of heirship of community property is made, the applicant must mail notice to all heirs and devisees whose addresses are reasonably available, and is responsible to anyone harmed by a failure to do so (§ 15-3-303A). Once a personal representative is appointed, that person must notify the heirs and devisees within 30 days (§ 15-3-705).
Effect of Informal Probate
Informal probate is conclusive as to all persons until superseded by an order in a formal proceeding (§ 15-3-302). Anyone who disagrees can start a formal testacy proceeding, generally within the later of 12 months after informal probate or three years after death (§ 15-3-108).
Formal Probate
Nature of a Formal Proceeding
A formal testacy proceeding is litigation to determine whether a decedent left a valid will (§ 15-3-401). It can be started to probate a will, to block an informal probate, or to have the court declare that the decedent died without a will. While a formal proceeding is pending, the registrar may not act on any informal application. A personal representative who was already appointed must stop making distributions after receiving notice of the formal proceeding, unless the petition asks to confirm the earlier appointment, and the petitioner can ask the court to restrain the personal representative entirely and appoint a special administrator (§ 15-3-401).
Notice and Objections
Notice of the hearing must go to the surviving spouse, children, other heirs, devisees and executors named in any will, and any existing personal representative. If the fact of death may be in doubt, the court can require notice by registered mail to the alleged decedent and a diligent search (§ 15-3-403). Anyone opposing the probate must state the basis in written objections (§ 15-3-404). If no one objects, the court may enter its order on the strength of the pleadings (§ 15-3-405).
Proving the Will and Burdens of Proof
A self-proved will, signed with a notarized affidavit, is conclusively presumed to satisfy the signature requirements, and presumed (subject to rebuttal) to meet the other execution requirements, without testimony from the witnesses, unless there is proof of fraud or forgery (§ 15-3-406). In a contested case, the person offering the will must prove it was properly executed. The contestant bears the burden of proving lack of testamentary intent or capacity, undue influence, fraud, duress, mistake, or revocation (§ 15-3-407).
Lost Wills and Multiple Wills
Because informal probate requires the original will to be in the registrar’s possession (§ 15-3-303), a lost will must be established in a formal proceeding, where the court makes findings of its provisions (§ 15-3-409). The court can probate more than one instrument if none expressly revokes the others (§ 15-3-410), and can determine that part of an estate passes by intestacy when a will does not dispose of all of it (§ 15-3-411).
Finality and Vacating an Order
A formal testacy order is final as to everyone on all issues the court considered or could have considered (§ 15-3-412). It can be reopened in narrow circumstances, such as a later-discovered will whose proponents were unaware of the earlier proceeding, or an heir who was omitted and did not know of the death or the proceeding. A petition to vacate must be filed before the earliest of the order approving final distribution (or 6 months after a closing statement), the three-year limit to open probate, or 12 months after the order. For other good cause, an order can be vacated within the time allowed for appeal (§ 15-3-413).
Formal Proceedings on Who Serves
Disputes over who should be personal representative are decided in a formal proceeding. If filed before an appointment, it stays any informal appointment. If filed after, the existing personal representative must stop acting except to preserve the estate. The court then appoints the person entitled under the priority statute and can terminate an improper appointment (§ 15-3-414).
Supervised Administration
Supervised administration is a single, continuous court proceeding that lasts until the estate is closed (§ 15-3-501). It is ordered if the will directs it, unless circumstances have changed, or when the court finds supervision necessary to protect the people interested in the estate (§ 15-3-502). A supervised personal representative may not make any distribution without prior court order, and any other limits on their authority are endorsed on the letters (§ 15-3-504). It is used in a small minority of Idaho estates.
Special Administrators
When an estate needs protection before a regular personal representative is in place, or when the regular representative cannot or should not act, a special administrator can be appointed (§ 15-3-614):
- Informally by the registrar, to protect the estate before a general personal representative is appointed. This administrator’s job is to collect, preserve, and account for the assets and hand them over to the general personal representative (§ 15-3-616).
- Formally by the court after notice and hearing, or without notice in an emergency. This administrator has the powers of a general personal representative except as the order limits them (§ 15-3-617).
If a will is pending probate, the executor named in it is appointed special administrator if available and qualified (§ 15-3-615). The appointment ends as the order provides or when a general personal representative is appointed (§ 15-3-618).
How I Can Help
I help clients choose the right type of proceeding at the start, which often determines how smoothly the rest of the estate goes, and I handle both uncontested informal filings and contested formal hearings. Request a consultation to discuss the estate you are dealing with.
More Idaho probate topics: Idaho probate guide · Small estates · Personal representative duties · Creditor claims · Closing an estate · Idaho estate planning · Idaho probate litigation
This page provides general information about Idaho probate law, based on Idaho Code Title 15, Chapter 3 as of 2026, and is not legal advice. Other chapters of the Idaho Code, court rules, and case law also affect probate matters. Every estate is different; consult an attorney about your situation. Reading this page does not create an attorney-client relationship.