An upturned collar is an otherwise flat, protruding collar of either a shirt, jacket, or coat that has been turned upward. In recent years, some have perceived it as a fashion statement. Before the early twentieth century, most shirt collars were turned up in some manner.

 Poker TopMen and women alike wore tall, stiff collars (as much as three inches tall), not unlike a taller version of a clerical collar, made either of starched linen, cotton, or lace. The writer H. G. Wells remarked in his 1902 book Kipps that these "made [the] neck quite sore and left a red mark under [the] ears." Between the late nineteenth century and mid-twentieth century, men's collars were often detachable from their shirts, connected only by two removable collar studs (one in front and one in back). Detachable collars were very stiff, and either stood straight up (as in a Hamilton collar) or were pressed over at an ironed-in, starched crease (as in a Fremont collar). After World War II, mass-production gradually phased out detachable collars from ordinary dress shirts. Occasionally, one can still find detachable collar formal shirts, designed to be worn with a tuxedo or evening dress. Brooks Brothers sells such a shirt at a few locations. Lapels on jackets and coats, which resemble (and derive from) a longer collar, were and are also occasionally worn turned up. The frock coat of the eighteenth and nineteenth century often had a solid lapel that was always turned up.

Gradually, toward the mid-to-late nineteenth century, however, lapels became folded down and "pieced out," in the peak, notched, or shawl lapel that one sees to this day. Today, however, a jacket lapel's ability to be turned up helps to provide an extra modicum of warmth when weather is cold or windy. With the advent of the tennis shirt, however, the upturned collar took on a whole new purpose. In 1929 René Lacoste, the French 7-time Grand Slam champion, decided that the stiff dress shirts and ties usually worn by tennis players were too cumbersome and uncomfortable for the tennis court. Instead, he designed a loosely-knit pique cotton shirt with an un-starched, flat protruding collar and a longer shirt-tail in back than in front. This came to be known as the tennis shirt. Lacoste's design called for a thick pique collar that one would wear turned up in order to block the sun from one's neck. Thus, the tennis shirt's upturned collar was originally designed by the inventor of the tennis shirt, himself, for ease and comfort on the tennis court, aiding the player by helping to prevent sunburn and hyperthermia. Gradually, as tennis shirts became more popular and were produced more widely, their use transcended tennis and was adopted for golf, polo, other sports, and everyday life. As the tennis shirt entered the popular culture, wearers were less apt to turn up their collar to block the sun if not wearing the shirt during sport or outdoor activity. Thus, most people began to wear a tennis shirt without the collar turned up, or turning them up only when involved in sport. The professional golfer Fuzzy Zoeller is known for this practice today; as the golf shirt is a looser-fitting descendant of René Lacoste's tennis shirt, off the course Zoeller wears his golf shirt's collar turned down, whereas one often observes him with an upturned collar while he is playing.

 In 1980, Lisa Birnbach published The Official Preppy Handbook, in which she extolled the "virtues of the upturned collar." According to Ms. Birnbach, rather than being a sports innovation, the upturned collar on a tennis shirt was simply a signal that the wearer is a "preppy". Despite this obviously tongue-in-cheek characterization, Ms. Birnbach did correctly identify that one was more likely to view an upturned collar on the beaches of Nantucket than one would in middle America. The book was a bestselling sensation. As a result, many people outside of the "preppy" enclaves of New England began emulating the style espoused in and categorized by Ms. Birnbach. As such, ordinary people in middle America who would not otherwise have done so began to wear the collars of their tennis shirts turned up as a popular culture trend, but not because of the collar's utilitarian purpose of blocking the sun. During the 1980s, many celebrities wore upturned collars. Joan Jett often upturned the collar of her leather jacket, as did Tiffany. Nevertheless, this style ultimately seemed to pass out of popular culture fashion by the middle of the 1990s. American adult male wearing the collar on his tennis shirt turned up as a part of a popular culture trend in the early 2000s.

 In very recent years, however, the upturned collar has undergone a resurgence in popularity as a trend in the popular culture, particularly in the United States, where some people began to refer to it as a "popped collar". It also gained popularity as a trend in Europe (perhaps after football star Eric Cantona). Although the upturned collar no longer seems to be in vogue with the majority of European youth, older people still frequently wear upturned collars. Recently, certain Americans still perceive the upturned collar to be a "preppy" status symbol. This trend seems no longer to be limited to tennis shirts, as some people turn up the collars of shirts not designed to be worn that way, most notably Europeans above the age of 35. Today, some Americans regard the trend as having worn out, and thus the wearer of an upturned collar can be the object of mockery and scorn. Still, others continue to turn up their collars as a popular culture fashion. This has been bolstered by publicity from retailers with a middle-class clientele, such as J. Crew, Abercrombie & Fitch, and American Eagle Outfitters (although Abercrombie & Fitch company styling requirements for the 2006 Holiday floorset officially said that their workers should not be turning their collars up [1]).

Of course, even amidst this environment, there are many people throughout the Western world who do not turn up the collars of their tennis shirts as a popular culture trend (and are often mystified by its adoption as a trend), but rather continue to do so either out of lifelong habit or for the sport use for which it originally was designed.