Washington State Will Requirements: What Makes a Will Legally Valid

A will that fails to meet Washington's legal requirements is treated as if it doesn't exist. The estate then falls under intestate succession — state law decides who inherits, regardless of what the document says or what the deceased intended. Understanding what makes a Washington will legally valid is essential whether you are drafting one, or whether you are an executor trying to determine if the document you found is actually enforceable.

Who Can Make a Will in Washington

Washington's baseline requirements for making a will are set by RCW 11.12.010:

• Age: The testator (the person making the will) must be at least 18 years old, or be a legally emancipated minor, or be or have been legally married
• Mental capacity: The testator must be of "sound mind" — they must understand the nature of making a will, know what property they own in general terms, understand who their natural heirs are, and be capable of forming a coherent plan for disposing of their property

If any of these conditions is absent at the moment of signing, the will may be challengeable in probate court. "Sound mind" does not require perfect mental health — a person with early-stage dementia may still have the legal capacity to make a valid will on a lucid day. However, a will signed during a period of documented incapacity is vulnerable to a will contest.

The Standard Will: Written, Signed, and Witnessed

The most legally durable type of will in Washington is a formally executed typewritten or printed will. It must satisfy all of the following:

Writing

The will must be in writing. Oral (verbal) wills — sometimes called nuncupative wills — are not recognized in Washington.

Testator's Signature

The will must be signed by the testator. If the testator cannot physically sign, they can direct another person to sign on their behalf in their presence. The signature must appear at the end of the document.

Two Witnesses

A valid Washington will requires two witnesses. The witnesses must:

• Be present at the same time when the testator signs (or acknowledges a prior signature)
• Sign the will in the presence of the testator
• Be 18 years of age or older
• Not be legally incompetent

Can a beneficiary be a witness? A beneficiary who signs as a witness does not void the will in Washington. However, the beneficiary-witness may be subject to a "purging statute" that limits what they can receive under the will to the amount they would receive under intestate succession — potentially reducing or eliminating their bequest. To avoid this complication, witnesses should not be people named in the will.

No Notarization Required (But Beneficial)

Washington does not require notarization to create a valid will. However, notarization — combined with a specific self-proving affidavit — makes probating the will significantly easier.

The Self-Proving Affidavit

A self-proving will includes a notarized declaration signed by the testator and witnesses stating that all formalities were observed. Under RCW 11.20.020, a self-proving will can be admitted to probate without requiring the witnesses to appear in court or submit declarations.

Without a self-proving affidavit, the probate court technically requires the testimony of at least one witness to admit the will. In practice, courts use the "Declaration of Witness to Will" form — a sworn declaration from a witness that can be submitted in writing rather than in person. But if witnesses have died or are unreachable, admitting a will without a self-proving affidavit becomes considerably more complicated.

For any professionally drafted will, the self-proving affidavit is standard. If you are reviewing an older will drafted without an attorney, check whether it includes notarized witness signatures. If it does not, the will can still be valid — but admitting it to probate will require additional steps.

Holographic Wills in Washington

Washington does not recognize holographic wills as a matter of statute. A holographic will is one that is entirely handwritten and signed by the testator, without the two-witness requirement. States like California, Texas, and Alaska recognize holographic wills. Washington does not.

A handwritten document in Washington — even one that clearly expresses the testator's wishes about distributing their property — is not a valid will unless it meets the same two-witness requirement as a typed will. If a deceased Washington resident left only a handwritten, unwitnessed document expressing their wishes, that document has no legal effect on the distribution of the estate.

What If the Will Is Lost?

Under RCW 11.20.070, a lost will can still be probated if sufficient evidence of its existence and content can be established. The PR must file a Petition for Probate of Lost Will, which triggers a requirement to give 20 days' advance written notice to all heirs, beneficiaries, and transferees before the court can act. This notice period allows anyone who disputes the claimed content of the lost will to come forward and contest the proceeding.

Proving the content of a lost will typically requires witness testimony, copies of the document (photocopies or electronic scans), and any other documentation that establishes what the will said and that it was properly executed. The court's standard is clear and convincing evidence.

The Mandatory Will Filing Requirement

Here is a requirement that surprises many Washington residents: even if you are not planning to open a formal probate case, anyone with custody of a deceased person's original will is legally required to deliver it to the Superior Court or to the named executor within 30 days of learning of the death. If the custodian is the named executor, the deadline is 40 days.

This filing obligation exists even when the estate is small enough that no probate is necessary — even when all assets pass through non-probate means and the will has no practical effect. The will is a public document once the testator dies, and Washington law requires it to be accessible.

Failure to deliver the will within the statutory period is technically a misdemeanor under RCW 11.20.010, though prosecutions for this specific violation are rare. The more practical concern is that holding a will creates civil liability if beneficiaries or heirs can show they were harmed by the delay.

Will Contests: Grounds for Challenging a Washington Will

A will can be challenged in Superior Court on the following grounds:

Lack of testamentary capacity: The testator lacked the legal mental capacity described above at the time of signing.

Undue influence: A third party exerted such pressure on the testator that their free will was overridden. Undue influence cases often arise when a caregiver, new romantic partner, or one adult child had significant control over a vulnerable testator.

Fraud or duress: The testator was deceived about what they were signing, or was threatened or coerced.

Improper execution: The will lacks the required signature or witnesses, or the witnesses were not present simultaneously when the testator signed.

Will contests must be filed within four months of the will being admitted to probate. A contestant who waits longer than four months loses the right to challenge, regardless of the merits.

Codicils: Amending a Will

A codicil is a formal amendment to an existing will. Under Washington law, a valid codicil must meet the same execution requirements as the original will — writing, signature, and two witnesses. Informal handwritten amendments to a typed will do not create valid codicils.

Executors administering an estate with both an original will and one or more codicils must probate all documents together. The codicil amends specific provisions of the original will; the remaining provisions of the original will remain in effect.

Storing a Will Before Death

Washington allows individuals to file their original will with the Superior Court Clerk for safekeeping before their death. The clerk charges a $20 fee and seals the will until the testator's death. This prevents the will from being lost, destroyed, or contested on the basis that a copy is not the original.

Filing a will with the court before death does not constitute probating the will — it is simply secure storage. The will is opened and admitted to probate only after death.

Understanding whether a will you've found is legally valid — and what the filing obligations are — is one of the first questions every executor faces. The Washington Probate Process Guide covers will validity, the filing requirement, and what to do in the first 30 days after a death, including how to handle a will contest or a missing original.

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