Grounds to Contest a Will: The Evidence-First Guide (2026)

What Are the Legal Grounds to Contest a Will?

A will can be contested on five legal grounds: lack of testamentary capacity, undue influence, fraud or forgery, improper execution, and revocation by a later instrument. Courts presume a signed will is valid. Displeasure with the outcome is never a ground. The contestant bears the burden of proving one of these five grounds with admissible evidence.

Key takeaways

• Fewer than 10% of litigated will contests result in the will being overturned; roughly 3% of all U.S. wills filed are disputed at all.
• Every ground requires a specific category of evidence — medical records, witness testimony, handwriting analysis, or execution documents.
• Deadlines are often shorter than people expect: California gives you 120 days from admission; Texas gives two years.
• A no-contest clause does not block a challenge supported by probable cause in most states, and is entirely unenforceable in Florida.
• A well-documented, properly executed will is the most effective protection against any of these five grounds.

Who Can Contest a Will? (Standing Comes First)

Before examining the grounds, confirm you have standing. Filing without it wastes time and money.

Standing generally requires a direct financial interest in the outcome. Three categories of people typically qualify:

1. Heirs at law — anyone who would inherit under your state's intestacy statute if the will were declared void (usually a spouse, children, or parents).
2. Beneficiaries under a prior will — if a later will reduced or eliminated your share under an earlier valid will, you have a financial stake in the outcome.
3. A surviving spouse asserting an elective share — most states protect a surviving spouse from being disinherited below a statutory minimum, and that spouse can always object.

In New York, standing is governed by Surrogate's Court Procedure Act § 1410, which limits objections to persons "whose interest in property or in the estate of the testator would be adversely affected by the admission of the will to probate." Simply being a family member who expected more is not enough.

The Five Grounds — Mapped to the Evidence You Actually Need

Most articles list the grounds. This table goes further: it maps each ground to the evidence required, who typically holds that evidence, and a realistic cost to gather it. Use this to pre-qualify your own case before calling a lawyer.

Ground	What you must prove	Key evidence	Typical cost to gather	Realistic odds
Lack of testamentary capacity	Testator did not understand (1) nature of a will, (2) extent of property, (3) natural heirs, or (4) how the will distributes assets — at the moment of signing	Medical records within 30–90 days of signing; physician testimony; attorney notes from signing	$3,000–$10,000 for record retrieval and expert review	Low–moderate; the legal standard is intentionally low
Undue influence	A third party destroyed the testator's free will so the will reflects the influencer's intent, not the testator's	Isolation evidence (call logs, visitor records); drafting attorney's file; prior estate plans; caregiver records	$5,000–$20,000+ for discovery	Moderate if circumstantial evidence is strong; nearly always settled
Fraud or forgery	Will was signed by someone else, or testator was deceived about what they were signing	Handwriting analysis; comparison with authenticated signatures; drafting history	$3,000–$8,000 for handwriting expert alone	Moderate–high for clear forgery; rare in attorney-drafted wills
Improper execution	Will did not comply with the state's signing and witnessing formalities	The will itself; witness testimony about the signing ceremony; notary records	$500–$2,000; often resolved on the face of the document	Highest for pro se wills; low for attorney-executed wills
Revocation / later will	A more recent, valid will exists that supersedes the one admitted to probate	The later will; attorney records; testimony of custodian	$1,000–$5,000 if the later will surfaces	High once the later will is produced and authenticated

A closer look at the hardest ground: testamentary capacity

The four-element test traces to Banks v. Goodfellow (1870), an English decision that U.S. courts across all 50 states have adopted. Under California Probate Code § 6100.5, the test is codified: the testator must understand the nature of the testamentary act, the extent of the property being disposed, the natural objects of their bounty, and the manner in which the will distributes that property — all at the moment of signing, not generally.

This is deliberately a low bar. A person can have a dementia diagnosis, be unable to manage their finances, and still sign a valid will during a lucid interval. Medical records showing cognitive decline are necessary but not sufficient: you must show incapacity at that specific signing date. That is why the doctor's notes from the week of signing, and the drafting attorney's observations, are the most valuable documents in any capacity challenge.

Undue influence: the circumstantial ground

Undue influence almost never happens in front of witnesses. Courts therefore allow it to be proved through circumstantial evidence: isolation of the testator, control of the testator's finances and healthcare, last-minute changes to a long-standing estate plan, the beneficiary's presence during attorney meetings, and a dramatic departure from the testator's expressed wishes toward family members. A rebuttable presumption of undue influence can arise when a confidential or fiduciary relationship existed between the testator and the new beneficiary.

Worked Example: The Caregiver Scenario

Facts. Margaret, 84, signed a new will three weeks before her death, redirecting a $750,000 estate almost entirely to her live-in caregiver. Her 2019 will had split the estate equally between her two adult children. The caregiver had moved Margaret to a new city 18 months earlier, and the children's phone calls went unanswered in the final year. The new will was drafted by an attorney the caregiver had arranged.

Evaluating each ground:

• Testamentary capacity: Neurology records from four months before signing documented moderate Alzheimer's disease. But the drafting attorney's notes describe Margaret as "alert and oriented" on signing day. Capacity is a genuine dispute, not a slam dunk.
• Undue influence: The strongest ground here. The caregiver controlled access to Margaret, arranged the attorney, was present in the waiting room during the appointment, and is the primary beneficiary. This pattern — isolation, control of communications, participation in drafting — is exactly what courts look for.
• Improper execution: The will had two witnesses. One was a neighbor, the other the caregiver's cousin. Witness eligibility (whether an interested witness disqualifies a bequest) varies by state; this deserves investigation but is unlikely to void the entire will.
• Fraud: No clear evidence of deception about what was being signed.

The math. Margaret's estate is in California. The children have 120 days from probate admission to file under Cal. Prob. Code § 8270. An attorney takes the case on a 35% contingency. If the case settles mid-discovery for 70% of the estate (roughly $525,000), the attorney's fee is ~$184,000 and the children each net ~$170,000 versus the $0 they would receive from the current will. The contest makes economic sense.

If the estate were $80,000 total, the same analysis would not support a contingency arrangement. At $80,000, a fully litigated contest could consume the entire estate in fees. Mediation or an early negotiated settlement would be the only rational path.

This cost-benefit calculation — comparing the realistic recovery against total litigation cost — is the single most important analysis to run before deciding to contest.

Filing Deadlines by State: Act Before You Calculate

Deadlines are non-waivable. A strong case filed one day late is dismissed.

State	Deadline	Triggering Event	Key Statute
California	120 days	Date will is admitted to probate	Cal. Prob. Code § 8270
Texas	2 years	Date of admission order	Tex. Estates Code § 256.204
New York	Before the decree admitting the will is entered	Citation served in probate proceeding	SCPA § 1410
Florida	3 months after notice to creditors; will contest timing varies	Probate opening	Fla. Stat. § 733.109
Pennsylvania	1 year from probate	Date of probate	20 Pa. C.S. § 908
Missouri	6 months after probate opened	Date of admission	Mo. Rev. Stat. § 473.083

State deadlines change; verify with a licensed attorney in your jurisdiction before relying on this table.

In New York, the practical rule is starker than any calendar date: once a citation is served on you, you must appear at the return date and preserve your right to object. Under SCPA § 1404, you may examine the will's attesting witnesses and drafting attorney before formally filing objections — and doing so does not trigger a no-contest clause.

No-Contest Clauses: What They Do and Don't Block

A no-contest clause (also called an in terrorem clause) strips a beneficiary of their inheritance if they challenge the will and lose. Enforceability falls into three camps:

Category	States (examples)	Effect
Unenforceable	Florida, Indiana	Clause is void; anyone may contest without forfeiture risk (Fla. Stat. § 732.517)
Probable-cause exception	California, Michigan, Arizona, Colorado	Clause enforced only if challenger lacked probable cause (Cal. Prob. Code §§ 21310–21315)
Strict enforcement	New York, Oregon	Clause fully enforced; narrow exceptions for forgery and challenges via a later will

The probable-cause exception is critical: if you have genuine evidence of fraud, incapacity, or undue influence, filing a challenge in a probable-cause state does not automatically cost you what you were already left.

Read our deeper breakdown in understanding the no-contest clause and, for witness rules that directly affect execution challenges, will witness requirements by state.

How to Contest a Will: Five Steps

1. Confirm standing. Identify whether you are an heir at law, a prior-will beneficiary, or a surviving spouse with elective share rights. Without standing, nothing else matters.
2. Gather preliminary evidence immediately. Request the decedent's medical records, prior estate planning documents, and any communications with the new beneficiary from the executor or attorney. Evidence degrades fast.
3. Check the deadline. Identify whether probate has been opened, and when. In California, your 120-day clock under Cal. Prob. Code § 8270 may already be running.
4. File a formal petition or objection. In most states, this means filing a written petition with the probate court, identifying your grounds and supporting evidence. In New York, this means filing under SCPA § 1410 before the decree is entered.
5. Pursue discovery or settlement. Depositions of witnesses, the drafting attorney, and the beneficiary reveal whether your case strengthens or weakens. Most cases settle here. If they don't, a bench trial before the probate judge decides validity.

If you're weighing a contest because a will was recently created under questionable circumstances, understanding the full probate process will help you anticipate what happens next regardless of outcome.

The best way to avoid being on either side of a will contest is a well-executed, clearly drafted will. You can create your will online through Pactlio's guided process, which produces a state-specific draft with execution instructions — or visit Pactlio Wills to learn how the review process works.

Common Mistakes to Avoid

• Waiting to see what happens. Every day after probate opens eats into your deadline. In California, 120 days sounds like a lot until you realize the clock may have started while you were grieving.
• Contesting on anger, not evidence. Courts presume wills are valid. Without specific evidence tied to one of the five grounds, a contest will be dismissed and you may owe the estate's legal fees.
• Ignoring a no-contest clause before filing. In strict-enforcement states like New York, filing without strong probable cause forfeits whatever you were left. Get a legal opinion before you file anything.
• Conflating unfairness with invalidity. A testator can leave the entire estate to a charity and disinherit all children — provided they had capacity, no one unduly influenced them, and the will was properly executed. Unfair is not illegal.
• Relying on verbal promises. "Mom said she'd leave me the house" is not a ground to contest. Oral statements about inheritance are generally unenforceable against a written, executed will.
• Missing the signing-day evidence window. In capacity and undue-influence cases, the most valuable evidence is from the days immediately around the signing: the drafting attorney's notes, medical records, and witness observations. Gather these before they are lost or destroyed.

Sources

• Cal. Prob. Code § 8270 — Will contest deadline, 120 days from admission: https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=PROB&sectionNum=8270.
• Cal. Prob. Code §§ 21310–21315 — No-contest clause probable-cause standard: https://leginfo.legislature.ca.gov/faces/codes_displayText.xhtml?lawCode=PROB&division=11.&title=2.&part=3.&chapter=2.
• Tex. Estates Code § 256.204 — Two-year deadline to contest: https://statutes.capitol.texas.gov/Docs/ES/htm/ES.256.htm
• Fla. Stat. § 732.502 — Execution of wills, witnessing requirements: https://www.leg.state.fl.us/statutes/index.cfm?App_mode=Display_Statute&URL=0700-0799/0732/Sections/0732.502.html
• Fla. Stat. § 732.517 — No-contest clauses unenforceable in Florida: https://www.leg.state.fl.us/statutes/index.cfm?App_mode=Display_Statute&URL=0700-0799/0732/Sections/0732.517.html
• N.Y. SCPA § 1410 — Who may file objections to probate: https://www.nysenate.gov/legislation/laws/SCP/1410
• Banks v. Goodfellow (1870) LR 5 QB 549 — Four-part testamentary capacity test (foundational common law): https://en.wikipedia.org/wiki/Banks_v_Goodfellow
• Justia — Testamentary capacity overview and elements: https://www.justia.com/probate/probate-litigation/will-contests/
• Justia — Undue influence in will contests: https://www.justia.com/probate/probate-litigation/will-contests/undue-influence/
• Keystone Law Group — Success rate of contesting a will: https://keystone-law.com/success-rate-of-contesting-a-will
• Policygenius — Cost to contest a will: https://www.policygenius.com/wills/how-much-does-it-cost-to-contest-a-will/

This article is general information, not legal advice. Laws vary by jurisdiction. Pactlio generates professional drafts for review — have a licensed attorney review anything important.