The handheld two-way radio was developed by the military from the backpack radios carried by infantry squad soldiers to guarantee the squad in touch with their commanders. In 1937, Canadian inventor Donald Hings was the first to create a portable radio signaling system for his employer CM&S. He called the system a "packset," although it was later called a "walkie-talkie." 

In 2001, Hines received the Order of Canada for the device's importance to the war effort. Hings handheld walkie-talkie" entered service in 1942, the result of a secret development effort that began in 1940.

The first device widely known as a "walkie-talkie" was developed by the U.S. military during World War II. It was created in 1940 by an engineering team from Galvin Manufacturing Company. The team, consisting of Marion Bond, Lloyd Morris, Bill Vogel, and Dan Noble, conceived the design using frequency modulation, with Henrik Magnusky as the lead RF engineer.

The first handheld walkie-talkie was invented in 1941 and was named the handie-talkie. The terms are often confused today, but originally walkie-talkies referred to back-mounted models, while handie-talkies referred to devices that could be held entirely in the hand. Both devices use vacuum tubes and are powered by voltage dry cell batteries.

After World War II, Raytheon developed a military replacement for the SCR-536, the AN/PRC-6. The AN/PRC-6 circuit uses 13 vacuum tubes (receiver and transmitter); The second set of 13 tubes is supplied with spare parts for the unit's operation. The unit is equipped with a crystal at the factory, which can be changed to a different frequency in the field by replacing the crystal and retuning the device. It uses a 24-inch whip antenna. There is an optional cell phone that can be connected to AN /PRC-6 via a 5-foot cable. An adjustable strap provides carrying and support while operating.

In the mid-1970s, the U.S. Marine Corps began an effort to develop a squad radio to replace the unsatisfactory helmet-mounted an /PRR-9 receiver and receiver/transmitter handheld AN /PRT-4 (both developed by the U.S. Army). The AN/PRC-68, first produced by Magnavox in 1976, was issued to the Marine Corps in 1980 and has also been adopted by the U.S. Army.

The abbreviation HT is usually used to refer to a portable handheld ham radio, while "walkie-talkie" is often used as a layman's term or specifically to refer to a toy. Public safety and commercial users often refer to their handheld devices simply as "radios." To avoid trademark infringement, other manufacturers use names such as "handheld transceiver" or "handdie transceiver" to name their products.