AB 1755 & the Manufacturer Opt-In: How It Changes Your California Lemon Law Deadline

Whether your car's manufacturer 'opted in' to California's AB 1755 procedures decides how long you have to file a lemon law claim — and it is the first thing to check. If your manufacturer opted in, you generally must file within one year after your written warranty expires, and in no case later than six years from the vehicle's original delivery. If it did not opt in, the traditional four-year deadline applies, running from when you discovered — or reasonably should have discovered — that the defect couldn't be fixed. Those two timelines can be years apart, so getting this wrong is one of the most common ways a valid-feeling claim gets time-barred.

Here's what AB 1755 actually changed, what 'opting in' means, and how to find out which deadline applies to your vehicle.

What AB 1755 changed

AB 1755 was signed into California law in September 2024 and phased in during 2025. Starting January 1, 2025, it added tighter mediation and discovery deadlines to lemon law lawsuits, and from April 1, 2025, it added a pre-litigation notice requirement for claims seeking civil penalties. The goal was to move disputes faster — but it also compressed the timeline in which owners must act.

The opt-in provision (SB 26)

Because the new framework raised concerns on all sides, the Legislature followed up with SB 26 in April 2025, which lets each manufacturer choose whether to be governed by the new AB 1755 procedures. This is the 'opt-in.' A manufacturer that elects in must apply the new rules to its California vehicles for a five-year period, and the mandatory mediation and discovery limits apply only to manufacturers that opted in. In other words, the rules that govern your case — including your filing deadline — can depend on a choice your manufacturer made.

How opting in changes your deadline

This is the part that matters most for owners:

• If your manufacturer OPTED IN: you generally must file within one year after your express (written) warranty expires — and in any event no later than six years from the vehicle's original delivery to the first owner.
• If your manufacturer did NOT opt in: the traditional four-year statute of limitations applies, and it runs from when you knew, or reasonably should have known, that the vehicle had a defect that couldn't be repaired.

The opted-in deadline is often the shorter and more surprising one. It is tied to your warranty's expiration, not the date you bought the car, so an owner who assumes they have four years can be well past the window without realizing it. When in doubt, treat your deadline as sooner rather than later.

How to find out if your manufacturer opted in

Opt-in status varies by manufacturer, and because it is an election that manufacturers make (and that lasts a set period), it can change over time. That's exactly why it shouldn't be guessed. We track the current status for each brand on its individual lemon law page, and the most reliable way to know which deadline applies to your specific vehicle — factoring in your warranty terms and purchase date — is a quick, free case review. Confirming your deadline early costs nothing and protects your claim.

Why this is the first thing to check

A lemon claim can be strong on the merits — a serious defect, a stack of failed repairs — and still be lost if it's filed too late. Because AB 1755 and the opt-in can quietly shorten the window, the deadline is the very first thing to pin down, before anything else. If your car has been in the shop repeatedly, don't wait to find out where you stand.