KTSW (89.9 FM) is a radio station broadcasting an Alternative format. Licensed to San Marcos, Texas, United States, it serves the San Marcos, Kyle, and New Braunfels areas. The station is an affiliate of Texas State University. Originally based in Old Main, KTSW 89.9 has moved into the newly renovated Trinity building in the fall of 2016. Its radio transmitter is located in New Braunfels on the Guadalupe County, Texas side.

KTSW

San Marcos, Texas
Broadcast area	San Marcos/New Braunfels, Texas
Frequency	89.9 MHz
Programming
Format	Alternative rock
Ownership
Owner	Texas State University
History
Call sign meaning	portmanteau meaning: Texas State and SouthWest (former name)
Technical information
Facility ID	61553
Class	C3
ERP	16,000 watts
HAAT	94 meters (308 ft)
Links
Website	ktsw.txstate.edu