If you're just doing a renewal, you can do it all online. You can also usually do it at an "On the spot" renewal location. Simply get the emissions test passed (if needed) and then log in to renewal express to complete the renewal or visit a location that participates in "On The Spot" renewals and get it done at the same time as your emissions test.
Setting an appointment has provided me the best DMV experiences I've ever had. I hope they keep doing it. If you don't have one, there are people standing outside who will help you make one, so you might as well.
Actually yes you do need an appointment
No you don't need an appointment, but you'll get attended faster if you do
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