The short answer: 90 days
When your vehicle passes, the station sends the result to the DMV electronically. According to the California Bureau of Automotive Repair (BAR), that certificate is valid for 90 days. In practice, that means you need to finish your DMV registration renewal or ownership transfer within 90 days of your passing smog check.
What if the 90 days run out?
An expired certificate does not count. If you wait too long, the DMV will ask for a new smog inspection, and you will pay for the test again. Plan on the 90 days being firm.
How to time your smog check
Your DMV renewal notice tells you whether a smog check is required and gives your due date. A simple plan:
- Get the smog check within the last few weeks before your registration is due, not months ahead.
- Leave enough time for a retest in case your vehicle does not pass the first time.
- Once you pass, renew right away online or at the DMV so the 90 days never becomes a problem.
Selling a car? Same 90-day window
When you sell a vehicle in California, the seller is generally responsible for providing a valid smog certificate. Because the certificate is only good for 90 days, do not test a car that will sit on the market for months. Test it when you have a serious buyer, or make sure you can finish the sale within the window.
Do I get a paper certificate?
The result goes to the DMV electronically, so there is nothing to mail in. You will also get a copy of your inspection report. Keep it until your registration is done, especially if you are renewing at a DMV office.
What if I fail?
A failed test does not use up your time, because only a passing result creates a certificate. Fix the problem, then come back for a retest. Our failed smog check help page explains the steps.
Get your smog check at Blaze Smog
Blaze Smog is opening soon in the South Bay. Walk-ins are welcome Monday to Saturday, 8 AM to 5 PM, so you can fit your smog test into the right week without booking ahead.
Sources: the California Bureau of Automotive Repair and the DMV smog check pages. Rules and fees can change, so always check your DMV renewal notice for what applies to your vehicle. This article is general information, not legal advice.
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Read articleNeed a smog check? Just drive in.
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