Each state has its own laws about wills. For example, in some states, a will may be handwritten, while in others, it is not valid. Some states require witness signatures, and others do not.
The Revised Code of Washington Chapter 11.12 defines what makes a will valid in the state.
A valid will
Only an adult (at least 18 years old) may create a will. There must be at least two witnesses of the will, and they may not have any interest in the will.
Under most instances, a will must be written, but cannot be handwritten. A handwritten, or holographic, will is not valid in Washington.
A nuncupative will is an oral will, and it can only be in effect if the testator’s personal property is no more than $1,000. It cannot designate real estate distribution. A U.S. servicemember or someone employed on a Merchant Marine vessel can use a nuncupative will to dispose of personal property and wages.
Two witnesses must be able to verify that the testator made the will in front of them and at the time of the testator’s last sickness. Within six months of the testator speaking his or her last wishes, someone must write the will, and proof offered. The surviving spouse and heirs-at-law must receive a citation so that they can contest the will if they so choose.
There are a number of reasons why a person may want to write a new will and revoke the old one, or to revoke some portion of it. In Washington, the testator may revoke the old by creating a new one that says specifically that it replaces the original or replaces it through the changes made.
A testator may revoke a will through destroying it, too, whether that be through burning, tearing or otherwise obliterating it. The testator may have someone else do it for him or her as long as it is done in his or her presence and there are two witnesses who can attest to the facts of its destruction.
If the testator revokes the entire will, the codicils also become revoked unless this would not be consistent with the testator’s intentions.