People sometimes ask us when the busy smog months are, as if emissions testing ran on a calendar like ski season. It does not. Every vehicle in the Reno and Sparks testing area has its own clock, and that clock is the registration expiration date printed on the card in the glove box. Once you know your date, the rest is easy to plan.
The rule in one paragraph
The Nevada DMV requires an annual emissions test at registration renewal for vehicles based in the urban parts of Washoe and Clark counties. In Washoe that means Reno, Sparks, Washoe Valley, most of the county west of Washoe Valley and everything south of the 40th parallel (Nevada DMV emission page). Gasoline vehicles 1968 and newer are tested, along with diesels up to 14,000 pounds GVWR. A brand-new vehicle skips its first three registrations, and a hybrid skips its first five model years (Nevada DMV).
So your smog season is one specific month a year, and it repeats.
The two numbers that set your window
The first number is 90. A passing test is valid for 90 days under NRS 445B.800, so a test in the spring for a registration that expires in late summer is wasted. The second number is 35. The DMV's online renewal page lets a vehicle renew about 35 days before expiration (Nevada DMV online renewal).
Put those together and the sweet spot is the month before your registration expires. Test then, and the result is fresh, the online renewal is open, and you are not racing the deadline.
- Find the expiration date on your registration card or the DMV notice
- Count back about a month: that is your testing window
- Pass the test at one of our Reno smog check bays
- The result goes to the DMV electronically, and you renew
Doing both on the same trip
A lot of reviewers describe the test and the renewal as one errand. Megan L. went to the Longley service center for a smog and registration renewal and called the service quick and efficient (Google review). Karla S. was glad the Mae Anne service center was able to process her registration renewal with the DMV (Google review). Christine M. got her car smogged and registered and said she will be back next year (Google review).
If you want to renew on the spot, call the service center before you come to make sure it can process the renewal that day. Otherwise, the result reaches the DMV electronically and you can renew online from the parking lot.
Pairing it with the oil change
Because the smog check comes once a year, it is a natural anchor for the rest of your maintenance. Shannon R. called the Longley service center a good place for an oil change and one stop for smog and registering a car (Google review). If the oil sticker is close, do both in one pull-in. If the check engine light is on, sort that out first; the check engine light guide explains why it matters for the test.
Smog checks are on the menu at Reno Northwest on Mae Anne Avenue and Reno South on Longley Lane. When your month comes around, pull into a Reno service center with no appointment.
Sources
- dmv.nv.gov/emission.htm (Nevada DMV Emission Control Program: Washoe and Clark testing areas, exemptions, 90-day validity, 2026 fee caps, read 2026-10-15)
- leg.state.nv.us/nrs/nrs-445B.html (NRS 445B.700-445B.845, Nevada emissions law: annual testing after the fourth registration, 90-day validity, read 2026-10-15)
- dmvapp.nv.gov/dmv/vr/regrenewal/vrrenewal/vr_ren_input.aspx (Nevada DMV online registration renewal: results sent electronically, eligible about 35 days before expiration, read 2026-10-15)
- maps.google.com/maps?cid=11279543644516200798 (Google Business Profile, Reno South at 4993 Longley Ln: 4.8 stars, 339 reviews, hours, read 2026-10-15)
