Birdwell is a American surf clothing company, headquartered in California, makers of Birdwell Beach Britches. Founded by Carrie Birdwell Mann in 1961, the company manufactures and sells customised heavy-duty swimsuits, which are sold internationally. With four basic models, various fabrics, including Surfnyl, Tectyl, heavy nylon, sailcloth, and canvas, more than 40 colours, and various other options, the combinations that can be created are nearly endless. Justifiably, the company's motto is "We don't build 1000 things. We build one thing 1000 ways.".

The swimsuits themselves, which resemble board shorts, are paneled swimsuits, with waistbands resembling boxing trunks, always double-stitched, always with two layers of fabric. These shorts are known and favoured among surfers, lifeguards, and paddleboarders, due to their quick-drying design and extreme durability; with an estimated 10 years for average use, and 2-5 for more strenuous use.

On all of the trunks, there is a 2 square inch (50 mm) logo, of a stylised anthropomorphic surfboard, wearing, of course, Birdwell Beach Britches, nicknamed "Birdie".