Under the Washington medical malpractice statute of limitations, you have three years from the date of a healthcare provider’s error or one year from the date you discovered (or reasonably should have discovered) the resulting injury, whichever gives you more time. A separate eight-year outer limit cuts off almost all claims regardless of when you found out, with narrow exceptions for fraud, intentional concealment, and foreign objects left in the body. All of these rules come from RCW 4.16.350.1
The Three-Year Clock
The default filing window is three years from the date of the negligent act or failure to act. The clock starts on the date the error occurred, not when you first felt pain or noticed something was wrong. If a surgeon nicks a nerve during an operation on January 15, 2026, the three-year period begins that day and expires on January 15, 2029.
This deadline sweeps in a wide range of providers: licensed physicians, dentists, nurses, chiropractors, pharmacists, physical therapists, psychologists, physician assistants, nurse practitioners, and paramedics, along with the hospitals, clinics, nursing homes, and health maintenance organizations that employ them. Employees and agents acting within the scope of their jobs are covered too.
The One-Year Discovery Rule
Patients don’t always know right away that a medical error caused their injury. Washington builds a discovery provision into the same statute: you have one year from the date you discovered, or reasonably should have discovered, that your injury was caused by the provider’s mistake. Your deadline is whichever runs out later, the three-year window or this one-year discovery window.
Say a patient has persistent abdominal pain after surgery and is told for two years that it’s a normal part of healing. In year three, an imaging scan reveals a surgical sponge left inside the body. The one-year discovery period begins on the date of that scan, because that is when the patient reasonably learned the injury was tied to negligence. Even though more than three years have passed since the operation, the later-expiring discovery deadline controls.
The key phrase is “reasonably should have discovered.” You can’t ignore obvious warning signs and then claim you didn’t know. If your symptoms clearly pointed to a problem and a reasonable person in your position would have sought answers, a court may find the discovery clock started earlier than you’d like. If nothing about your situation would have prompted a reasonable person to suspect malpractice, the clock won’t start until something does.
The Eight-Year Outer Limit
This is where many patients get tripped up. Washington imposes a hard eight-year outer limit: no medical malpractice lawsuit can be filed more than eight years after the provider’s act or omission, regardless of when the patient discovers the injury. This is called a statute of repose, and it exists to give healthcare providers finality.
The discovery rule cannot push your deadline past this eight-year wall. If a diagnostic error occurred nine years ago and you just learned about it last month, the statute of repose has already closed the door. Only three narrow situations can override that cap.
Exceptions That Break the Eight-Year Cap
Three circumstances pause both the standard deadlines and the eight-year statute of repose:
- Fraud. If a provider committed fraud to hide the malpractice, the deadlines are paused until you have actual knowledge of the fraud. You then have one year from that date to file.
- Intentional concealment. If a provider deliberately concealed information to prevent you from discovering the error, the clock doesn’t start until you actually learn what was concealed, and you have one year from that point.
- Foreign objects. If a provider left something in your body that wasn’t intended to serve a medical purpose, the deadlines are paused until you actually learn about the object. One year from that discovery to file.
Notice the standard here is “actual knowledge,” not the looser “reasonably should have discovered” test from the general discovery rule. The clock starts only when you genuinely know about the fraud, concealment, or object. Once you do know, though, the one-year window is short.
The foreign object exception has an important limit: it covers objects not intended to have a therapeutic or diagnostic purpose. A surgical sponge or a broken instrument tip qualifies. A plate, screw, or stent that was deliberately placed but later caused complications likely does not, because those objects were placed intentionally as part of treatment.
Deadlines When the Patient Is a Child
When the injured patient is under eighteen, Washington’s general tolling statute, RCW 4.16.190, pauses the limitations period until the child reaches adulthood. The Washington Supreme Court confirmed in 2014 that this tolling protection applies to medical malpractice claims, striking down a prior legislative attempt to eliminate it.1 As a practical matter, an injured child has until their twenty-first birthday to file: the age of majority plus the three-year filing period.
There is a significant complication. RCW 4.16.350 states that a custodial parent or guardian’s knowledge is attributed to the minor child. If a parent knows, or reasonably should know, about the malpractice, that awareness can start the discovery clock against the child’s claim just as it would for an adult. A parent who learns of a surgical error when the child is three but takes no action cannot assume the child will have a fresh start at eighteen. The eight-year statute of repose also applies to minors’ claims.
Deadlines at a Glance
- Standard deadline. Three years from the provider’s act or omission.
- Discovery deadline. One year from when you discovered or should have discovered that your injury was caused by negligence. Your claim survives if either this deadline or the three-year deadline hasn’t expired.
- Absolute outer limit. Eight years from the act or omission.
- Fraud, concealment, or foreign object. One year from actual knowledge, even if the eight-year period has passed.
- Minors. Tolled until the child turns eighteen, but a custodial parent’s knowledge is attributed to the child.
Missing any of these deadlines is fatal to the claim. Washington courts have no discretion to extend them, and the statute closes with an unambiguous warning that any action not filed in accordance with these rules is barred.
What Does Not Delay Your Filing
Two procedural rules often confuse patients but do not change when the lawsuit itself must be filed. Washington requires mandatory mediation in medical malpractice cases under RCW 7.70.100, but mediation happens after the lawsuit is filed, as part of the pretrial process. A former law requiring ninety days’ written notice to the provider before filing was struck down by the Washington Supreme Court, so no pre-suit notice is currently required.
Washington also does not require a certificate of merit at the time of filing. The legislature once enacted such a requirement, but the state Supreme Court struck it down in 2009. Expert testimony is still essential to winning the case, but you secure the expert during litigation, not as a precondition to getting into court.