Will Contests in Idaho

Part of my Idaho Wills & Probate Overview.

By Ronald W. Brilliant, Attorney at Law · Licensed in Idaho, Nevada & California · Last reviewed: September 2026 against the Idaho Code as posted by the Idaho Legislature (July 1, 2026)

In This TopicIdaho Wills & ProbateTopic 6 of 15: Will Contests

A will contest is a court case over whether a person who has died left a valid will. In Idaho, this kind of case is called a formal testacy proceeding, which the Idaho Code describes as “litigation to determine whether a decedent left a valid will” (Idaho Code § 15-3-401). A “testacy proceeding” is a proceeding to establish a will or to determine intestacy, meaning that the person left no valid will (Idaho Code § 15-1-201(52)).

This topic matters to heirs, people named in a will, and anyone serving as the personal representative, a term that includes an executor or administrator (Idaho Code § 15-1-201(35)).

How a Will Contest Starts

A formal testacy proceeding may be started by an interested person filing a petition with the court (Idaho Code § 15-3-401). Interested persons include heirs, devisees (people named in a will to receive property), children, spouses, creditors, and others with a property right in or claim against the estate that may be affected by the proceeding (Idaho Code § 15-1-201(25)).

Under Idaho Code § 15-3-401, the petition may ask the court to do any of the following after notice and a hearing:

• Enter an order probating a will (§ 15-3-401).
• Set aside an informal probate of a will (§ 15-3-401).
• Prevent informal probate of a will that is the subject of a pending application (§ 15-3-401).
• Set aside a determination that the entire estate is community property and there is a surviving spouse (§ 15-3-401).
• Declare that the decedent died intestate, meaning without a valid will (§ 15-3-401).

A petition may seek formal probate of a will whether or not the same will or a conflicting will has already been informally probated (Idaho Code § 15-3-401). Until a formal order replaces it, an informal probate is conclusive as to all persons (Idaho Code § 15-3-302). To learn how informal probate works, see Informal vs. Formal Probate in Idaho.

Any party to a formal proceeding who opposes probate of a will for any reason must state those objections in his or her pleadings (Idaho Code § 15-3-404).

Deadlines for Contesting a Will

The main time limits from Idaho Code § 15-3-108 are summarized below.

Situation	Time limit
General rule for informal probate, formal testacy, and appointment proceedings	Not more than 3 years after the decedent’s death, with listed exceptions (Idaho Code § 15-3-108)
Contest of a will that was informally probated (and appointment of the person with priority if the contest succeeds)	The later of 12 months from the informal probate or 3 years from the decedent’s death (§ 15-3-108(3))
Proceedings to construe (interpret) a probated will, or to determine heirs of a person who died without a will	The § 15-3-108 limits do not apply (§ 15-3-108)

The court must find that the proceeding was started within the § 15-3-108 limit before it determines the decedent’s heirs and state of testacy (Idaho Code § 15-3-409).

Notice of the Hearing

When a formal testacy proceeding begins, the court sets a time and place for a hearing (Idaho Code § 15-3-403(1)). The petitioner must give notice to the surviving spouse, children, and other heirs; to the devisees and executors named in any will that is being or has been probated or offered for probate in the county, or that the petitioner knows was probated or offered elsewhere; and to any personal representative whose appointment has not ended (§ 15-3-403(1)). Anyone who filed a demand for notice under § 15-3-204 must also receive notice (§ 15-3-403(1)).

Unless a specific rule says otherwise, notice is given by mail or personal delivery at least 14 days before the hearing (Idaho Code § 15-1-401(a)(1)-(2)). If a person’s address or identity cannot be found with reasonable diligence, notice is published once a week for 3 consecutive weeks in a newspaper of general circulation in the county, with the last publication at least 10 days before the hearing (§ 15-1-401(a)(3)).

What Happens to the Estate During a Contest

While a formal testacy proceeding is pending, the registrar may not act on any application for informal probate of any will of the decedent or for informal appointment of a personal representative (Idaho Code § 15-3-401). The registrar is a magistrate or district judge (Idaho Code § 15-1-307).

Unless the petition also asks the court to confirm the earlier informal appointment, a personal representative who receives notice of the formal proceeding must not make further distributions of the estate while it is pending (Idaho Code § 15-3-401). A petitioner who wants a different personal representative may also ask the court to restrain the current one and appoint a special administrator (§ 15-3-401). Without such a request, or if it is denied, starting the formal proceeding affects only the personal representative’s power to distribute (§ 15-3-401).

If a personal representative or person nominated as personal representative defends or prosecutes a proceeding in good faith, whether successful or not, that person is entitled to receive necessary expenses and disbursements, including reasonable attorney’s fees, from the estate (Idaho Code § 15-3-720).

Who Has to Prove What

Idaho Code § 15-3-407 assigns the burden of proof in contested cases. Each party also carries the ultimate burden of persuasion on the matters for which it has the initial burden (§ 15-3-407).

Party	What that party must establish
Proponents of a will (those asking that it be probated)	Prima facie proof of due execution in all cases; if they are also petitioners, prima facie proof of death and venue (Idaho Code § 15-3-407)
Contestants of a will (those opposing it)	Lack of testamentary intent or capacity, undue influence, fraud, duress, mistake, or revocation (§ 15-3-407)
Petitioners seeking to establish intestacy	Prima facie proof of death, venue, and heirship (§ 15-3-407)

If a will is opposed by a petition to probate a later will that revokes it, the court first decides whether the later will is entitled to probate (Idaho Code § 15-3-407). If a will is opposed by a petition for a declaration of intestacy, the court first decides whether the will is entitled to probate (§ 15-3-407).

Witness Testimony and Self-Proved Wills

In a contested case where evidence about the signing of an attested will that is not self-proved is needed, the testimony of at least one attesting witness is required, if that witness is within the state, competent, and able to testify (Idaho Code § 15-3-406(a)). Due execution of an attested or unattested will may also be proved by other evidence (§ 15-3-406(a)).

If the will is self-proved, compliance with the signature requirements is conclusively presumed, and the other execution requirements are presumed subject to rebuttal, without testimony from any witness, unless there is proof of fraud or forgery (Idaho Code § 15-3-406(b)). To learn how wills are signed and self-proved in Idaho, see Making a Valid Will in Idaho.

Jury Trial

If duly demanded, a party is entitled to a jury trial in any proceeding with a disputed question of fact on which any party has a constitutional right to a jury (Idaho Code § 15-1-306).

The Court’s Decision

After notice and any necessary hearing, if the court finds that the testator is dead, venue is proper, and the case was filed on time, it determines the decedent’s domicile, heirs, and state of testacy (Idaho Code § 15-3-409). Any will found to be valid and unrevoked is formally probated (§ 15-3-409). When a lost will is established, the court must find its provisions and file and record those findings (§ 15-3-409).

If two or more instruments are offered before a final order, more than one may be probated if neither expressly revokes the other or contains provisions that work a total revocation by implication (Idaho Code § 15-3-410). If the estate is or may be partly without a valid will, the court enters an order saying so (Idaho Code § 15-3-411). Rules on how a probated will is read are covered in How Wills Are Interpreted in Idaho, and rules on revocation are in Changing or Revoking a Will in Idaho.

When the Order Becomes Final

Subject to appeal and to vacation, a formal testacy order is final as to all persons on all issues the court considered or might have considered about whether the decedent left a valid will, and on the determination of heirs (Idaho Code § 15-3-412). For good cause shown, an order in a formal testacy proceeding may be modified or vacated within the time allowed for appeal (Idaho Code § 15-3-413).

The court must also hear a request to vacate the order and probate another will if the proponents of the later-offered will were unaware of it at the time, or were unaware of the earlier proceeding and received no notice except by publication (Idaho Code § 15-3-412(1)). If the court ordered intestacy for all or part of the estate, the determination of heirs may be reconsidered if a person was left out and was unaware of the relationship to the decedent, unaware of the death, or given no notice of any proceeding except by publication (§ 15-3-412(2)). These petitions must be filed before the earliest of the following (§ 15-3-412(3)):

• If a personal representative was appointed, entry of an order approving final distribution, or, if the estate is closed by statement, 6 months after the closing statement is filed (§ 15-3-412(3)(a)).
• The time when an original proceeding to probate a will can no longer be started under § 15-3-108 (§ 15-3-412(3)(b)).
• 12 months after entry of the order to be vacated (§ 15-3-412(3)(c)).

“No-Contest” Clauses

In Idaho, a will provision that purports to penalize an interested person for contesting the will or starting other proceedings relating to the estate is unenforceable if probable cause exists for starting the proceedings (Idaho Code § 15-3-905).

Resolving Estate Disputes Under TEDRA

Idaho’s Trust and Estate Dispute Resolution Act, or “TEDRA,” provides nonjudicial methods for resolving trust and estate matters by agreement, and judicial resolution if agreement is not reached (Idaho Code § 15-8-101(2)). TEDRA supplements, and does not replace, the other procedures in Title 15 (§ 15-8-101(2)).

A TEDRA “matter” includes, among other things, questions about the construction of wills, a change of personal representative, and an accounting from a personal representative (Idaho Code § 15-8-103(1)(c)). If all parties agree on how to resolve a matter, the agreement must be in writing and signed by all parties, and it is binding and conclusive on all persons interested in the estate, subject to § 15-8-304 (Idaho Code § 15-8-302). Once the agreement or a memorandum of it is filed with the court, it is deemed approved and is equivalent to a final court order (Idaho Code § 15-8-303(2)).

In a TEDRA court proceeding, the court may, in its discretion, award costs, including reasonable attorney’s fees, to any party, paid by any party, from the estate or trust assets, or from a nonprobate asset involved (Idaho Code § 15-8-208(1)). For more on TEDRA agreements, notice, and virtual representation, see Idaho Trust and Estate Disputes (TEDRA).

How I Can Help

If you are thinking about challenging a will, or you need to defend one, I can review the documents and the timeline, explain the deadlines and burdens that apply under the Idaho Code, and handle the petitions, objections, and notices a formal testacy proceeding requires. I can also help you explore whether a written TEDRA agreement could resolve the dispute by agreement. Request a consultation to discuss your situation.

This page provides general information about Idaho wills and probate, based on the Idaho Code, and is not legal advice. Court rules and case law also affect these matters. Every situation is different; consult an attorney about yours. Reading this page does not create an attorney-client relationship.