With the exception of brands like American Apparel, most t-shirt mills do most– if not all– of their manufacturing outside of the United States. In fact, the majority of clothing that is sold today in America is made abroad.
Many of the nation’s top t-shirt mills, such as Hanes, Fruit of the Loom, Gildan, and so on, have outsourced the bulk of their manufacturing to Latin American (and occasionally even Asian) facilities. Some of the common countries for manufacturing latin america include Mexico, El Salvador, Honduras, Haiti, and so on.
The president of The Adair Group has been down to Honduras, and knows firsthand that t-shirt manufacturing is serious business down there. The international t-shirts mill have terrific facilities, and a workforce willing to work for far less money than Americans will. This makes it easier for mills to produce more for less, making for a less costly product stateside.
Most t-shirt manufactured abroad are made in countries that are geographically very close to the USA. Closer proximity makes for a quick turnaround time on production, and reduces freight costs as well. While countries in the far east can produce tees for an even lower price, the longer turnaround time makes manufacturing clothing in Asia less desirable.
While there are certainly brands that make clothing here in the USA, if it’s cheap t-shirts that you want, you’re buying goods that have almost certainly been made abroad.