Billboard began compiling the popularity of country songs with its January 8, 1944 issue. Only the genre's most popular jukebox selections were tabulated, with the chart titled "Most Played Juke Box Folk Records".
For approximately ten years, from 1948 to 1958, Billboard used three charts to measure the popularity of a given song. In addition to the jukebox chart, these charts included:
- The "best sellers" chart – started May 15, 1948 as "Best Selling Retail Folk Records".
- A "jockeys" chart – started December 10, 1949 as "Country & Western Records Most Played By Folk Disk Jockeys".
The juke box chart was discontinued in June 1957. Starting with the October 20, 1958 issue, Billboard began combining sales and radio airplay in figuring a song's overall popularity, counting them in one single chart called "Hot C&W Sides". The chart was published under the title Hot C&W Sides through the October 27, 1962 issue and "Hot Country Singles" thereafter, a title it would retain until 1990.
On January 20, 1990, the Hot Country Singles chart was put to 75 positions and began to be compiled entirely from information provided by Nielsen Broadcast Data Systems, a system which electronically monitors radio airplay of songs. Four weeks later, on February 17, the chart was retitled "Hot Country Singles & Tracks". Beginning with the January 13, 2001 issue, the chart was cut from 75 to 60 positions, and all songs on the chart at the time had their tally of weeks spent on the chart adjusted to count only weeks spent at No. 60 or higher. Effective April 30, 2005, the chart was renamed "Hot Country Songs".
Starting in 1990, the rankings were determined by Arbitron-tallied listener audience for each spin that a song received. The methodology was changed for the first chart published in 1992 to tally the amount of spins a song received, but in January 2005, the methodology reverted to the audience format. This change was brought on because of "label-sponsored spin programs" that had manipulated the chart several times in 2004.
The Hot Country Songs chart methodology was changed starting with the October 20, 2012 issue to match the Billboard Hot 100: digital downloads and streaming data are combined with airplay from all radio formats to determine position. A new chart, the Country Airplay chart, was created using airplay exclusively from country radio stations. Following the change, songs that were receiving airplay on top-40 pop were given a major advantage over songs popular only on country radio, and as an unintended consequence, such songs began having record-long runs at the top of the chart. The first song to benefit from this change was Taylor Swift's "We Are Never Ever Getting Back Together", which had been declining in popularity but shot up to number one on the chart the first week the change took effect and stayed there until it set an all-time record for the most weeks at No. 1 by a solo female. This was followed almost immediately by Florida Georgia Line's "Cruise", which had the longest stay at number one of any song in the country chart's history (24 weeks), until it was surpassed by Sam Hunt's "Body Like a Back Road" in 2017 (34 weeks). The record was subsequently broken by Bebe Rexha and Florida Georgia Line's "Meant to Be" in 2018 (50 weeks).
Billboard has not explicitly defined how it determines what songs qualify for the country chart and which ones do not, only that "a few factors are determined (...) first and foremost is musical composition" and that a song must "embrace enough elements of today’s country music" to qualify. (The 1990–2012 chart did not have such ambiguity, being objectively measured by airplay from specifically identified country stations alone.) A later statement from Billboard elaborated on what those "few factors" entailed: "most notably the song’s musical composition, but also how the song is marketed and promoted, the musical history of the artist, airplay the song receives and how the song is platformed on streaming services." The 2019 country rap record "Old Town Road" by Lil Nas X was a subject of controversy over this ambiguous standard after it initially appeared on the country chart, where it debuted and peaked at number 19, before Billboard took the song off subsequent charts, claiming it had made a mistake in including it. The song gained popularity through viral memes rather than radio, as only one country station, Radio Disney Country, had played it at the time of the charting.