Beginning on July 1, there is a parking fee at San Marcos City Park that will apply to non-residents of the city. Parking will be free for the first 30 minutes, then $5.00 for up to one hour, $10.00 for up to 2 hours, or $15.00 for up to all-day. A flat fee of $25.00 will apply for holiday weekends and Texas State University special events. Payment may be made by using an on-site kiosk or a PayByPhone app.
You can read more about this HERE or HERE.
City of San Marcos