Area guide

Buying a used car in San Marcos, TX

San Marcos, TX is in Hays County, with a population of 77,830 (2025 Census), about 31 miles from downtown Austin, about 48 miles from downtown San Antonio. Main roads: I-35, SH 80, SH 123, SH 21, RR 12.

Buying a Used Car in San Marcos, TX: Local Guide

Photo: Larry D. Moore, CC BY 4.0, via Wikimedia Commons (cropped)

Short answer. Buy from a licensed dealer or a private seller who holds the title in their own name, run the VIN for recalls and title brands, get an inspection, and file the title at the Hays County tax office within 30 days. Hays County is not on the Texas emissions program list, so no emissions test is required to register there.

About San Marcos, TX

  • Home of Texas State University; Fall 2026 preliminary enrollment 47,513.
  • The main Hays County Tax Office is in San Marcos at 712 S Stagecoach Trail, Suite 1120.

Guides for San Marcos, TX buyers

Texas rules that apply in San Marcos, TX

  • Title transfer deadline. In a private sale, the buyer must title the vehicle in their name within 30 days from the date of sale. The seller gives the buyer a properly signed title (with date of sale and odometer reading) and a signed Form 130-U showing the sales price, and the buyer files at the county tax assessor-collector office.
  • Sales tax. Texas motor vehicle sales tax is 6.25 percent of the sales price minus any trade-in allowance. In a dealer sale, the dealer collects the tax and remits it to the county; in a private sale, the buyer pays the county tax assessor-collector when titling.
  • New to Texas. New residents have 30 days from moving to Texas to register their vehicle, and must get a Texas driver license within 90 days of moving to the state.
  • Inspection. Under House Bill 3297, non-commercial vehicles no longer need a safety inspection to register, starting January 1, 2025. Instead, all non-commercial vehicles pay a $7.50 inspection program replacement fee at registration; vehicles never registered before pay $16.75 to cover the first two years.

Where to title and register

Hays County Tax Office - San Marcos (main)
712 S Stagecoach Trail, Suite 1120, San Marcos, TX 78666
Official site

Next steps

Frequently asked questions

Do I need an emissions test in San Marcos, TX?

Hays County is not on the Texas emissions program list, so no emissions test is required to register there.

Where do I transfer a car title in San Marcos, TX?

At the Hays County tax assessor-collector, which handles titles and registration. Address and link are on this page.

Can Hunt Auto Group sell me a car in San Marcos, TX?

No. This site is educational. We are not a licensed Texas dealer and do not sell or arrange the sale of vehicles in Texas.

Sources

Educational content. Anthony does not sell, broker or arrange vehicle sales in Texas. Confirm fees and rules with the office named in each source before you pay anything.

Want a personalized car guide?

Message Anthony on WhatsApp with your budget and what you need. Free, honest advice in English or Spanish. He doesn't sell cars.

Anthony Hunt

Anthony Hunt

Web developer and car enthusiast in Austin, Texas. Anthony has spent the last year and a half around used cars and auctions, digs into every rule and recall so you don't have to, and knows people across the car business. Need help choosing a car? Ask him, it's free.

anthonyhunts.com
Chat with Anthony on WhatsApp