California Resident Purchasing Car in New York

You've almost got it covered. Yes, you'll need a smog check when you bring the vehicle to California, and if this is a new vehicle, it must be 50-state emissions certified (California). This does not apply if the vehicle is used. Used vehicles are exempt from needed to be "California Emissions Certified" and can be registered in CA after passing a California emissions inspection (smog check). Check the vehicle's Underhood Emissions Label for certification or ask the seller.

The only additional requirement when registering an out-of-state vehicle in California (for the first time) is a VIN Verification. A VIN verification is the simple process of matching up the vehicle's identification number (on the chassis; public VIN) with that of the VIN identified on its out-of-state title, but it can't be done by the vehicle's owner. A VIN verification can only be obtained at a California DMV office, California Highway Patrol Station or certified California VIN verification facility, and with appointment.

Once the vehicle's VIN is verified, you'll be issued a REG 31 (Verification of Vehicle). This document must be submitted to the DMV along with your out-of-state title, a REG 343 (Application for California Title) and the smog certificate. Note, California smog stations transmit electronic proof of smog inspection to the DMV. It is not necessary to submit a hard-copy of your smog certificate, but it is very important to keep it for your records or in case DMV systems do not show electronic proof.

Related Material

Online Vehicle Title Transfer (CA-to-CA)
California Title Transfer Quick Guide
California Smog Check Requirements
Commonly Used DMV Forms