"White Christmas" is an Irving Berlin song reminiscing about an old-fashioned Christmas setting. The version sung by Bing Crosby is the best selling single of all time.

Accounts vary as to when and where Berlin wrote the song. One story is that he wrote it in 1940, poolside at the Biltmore hotel in Phoenix, Arizona. He often stayed up all night writing — he told his secretary, "Grab your pen and take down this song. I just wrote the best song I've ever written — heck, I just wrote the best song that anybody's ever written!"

The first public performance of the song was also by Crosby, on his NBC radio show on Christmas Day, 1941 and the recording is not believed to have survived. He recorded the song with the John Scott Trotter Orchestra and the Ken Darby Singers for Decca Records in just 18 minutes on May 29, 1942, and it was released on July 30 as part of an album of six 78-rpm songs from the film . At first, Crosby did not see anything special about the song. He just said "I don't think we have any problems with that one, Irving."

The song initially performed poorly and was overshadowed by the film's first hit song: "Be Careful, It's my Heart". By the end of October 1942, however, "White Christmas" topped the "Your Hit Parade" chart. It remained in that position until well into the new year. (It has often been noted that the mix of melancholy — "just like the ones I used to know" — with comforting images of home — "where the treetops glisten" — resonated especially strongly with listeners during World War II. The Armed Forces Network was flooded with requests for the song.)

In 1942 alone, Crosby's recording spent eleven weeks on top of the Billboard charts. The original version also hit number one on the Harlem Hit Parade for three weeks, Crosby's first-ever appearance on the black-oriented chart. Re-released by Decca, the single returned to the #1 spot during the holiday seasons of 1945 and 1946 (on the chart dated January 4, 1947), thus becoming the only single with three separate runs at the top of the U.S. charts. The recording became a chart perennial, reappearing annually on the pop chart twenty separate times before Billboard Magazine created a distinct Christmas chart for seasonal releases.

Following its prominence in in the musical Holiday Inn, the composition won the Academy Award for Best Original Song. In the film, Bing Crosby sings "White Christmas" as a duet with actress Marjorie Reynolds, though her voice was dubbed by Martha Mears. This now-familiar scene was not the moviemakers' initial plan; in the script as originally conceived, Reynolds, not Crosby, was to sing the song.

The familiar version of "White Christmas" most often heard today is not the one Crosby recorded in 1942. He was called to Decca studios on March 18, 1947, to re-record the track; the 1942 master had become damaged due to its frequent use. Efforts were made to exactly reproduce the original recording session, and Crosby was again backed by the Trotter Orchestra and the Darby Singers. Even so, there are subtle differences in the orchestration, most notably the addition of a celesta and flutes to brighten up the introduction.

Crosby was dismissive of his role in the song's success, saying later that "a jackdaw with a cleft palate could have sung it successfully." But Crosby was associated with it for the rest of his career. Another Crosby vehicle — the 1954 musical White Christmas— was the highest-grossing film of 1954.

Crosby's "White Christmas" single has been credited with selling 50 million copies, the most by any release. The Guinness Book of World Recordslists the song as a 100-million seller, encompassing all versions of the song, including albums. Crosby's holiday collection Merry Christmaswas first released as an LP in 1949, and has never been out-of-print since. However, due to incomplete record keeping before 1958, "White Christmas" is officially listed as the second best-selling single worldwide.

"ItsRanked" ranked Crosby's "White Christmas" as the number one Christmas song on its Top 40 Christmas Songs of all time. In 1999, National Public Radio included it in the "NPR 100", which sought to compile the one hundred most important American musical works of the 20th century. In 2002, the original 1942 version was one of 50 historically significant recordings chosen that year by the Library of Congress to be added to the National Recording Registry.

The recording was broadcast on the radio on April 30, 1975, as a secret, pre-arranged signal precipitating the U.S. evacuation of Saigon (see Fall of Saigon).

Irving Berlin's opening bars are often dropped in many recordings, but are included on A Christmas Gift for You from Phil Spector, sung by Darlene Love.

There's never been such a day, in Beverly Hills, L.A., But it's December the twenty-fourth,—, And I am longing to be up North—

Keane's version also did include the introduction, but changed lyrics to give the song a melancholic feeling:

Seems everyone wears a frown, for Christmas in London town, It reminds me each time I roamed., I'm longing to be back home

The Drifters' 1954 cover of "White Christmas" showcased the talents of lead singer Clyde McPhatter and the bass of Bill Pinkney. Their recording of the song peaked at #2 on Billboard’s R&B chart in December 1954, and returned to the same chart in the next two years. In December 1955, "White Christmas" became the Drifters' first of 34 singles to register in the mainstream Hot 100 chart. For decades, the Drifters' version was primarily heard on R & B radio stations, getting little exposure elsewhere. The song received a boost in the early 1990s, when it was prominently featured in the film Home Aloneduring a scene in which the lead character Kevin is applying his father's aftershave while mouthing the lyrics. Radio stations formats as diverse as oldies, adult contemporary, Top 40, and country began playing the Drifters' version. The song was later featured in the film The Santa Clause.

Andy Williams charted on the Christmas Singles chart in 1963 (#1) and 1967 (#22) with his version. The B-Side was his version of The Christmas Song. In 1963, Jimmy McGriff recorded the song for his album "Christmas With McGriff".

In 2006 was covered by Twisted Sister feat Doro Pesch and was released on their album A Twisted Christmas, with German/English lyrics.

Andrea Bocelli recorded the song for his first holiday album, My Christmas, in 2009. The song debuted at No. 30, on the Portuguese Singles Chart, spent the 2 following weeks at No. 19, then rose to No. 18, on its forth week, before reaching No. 16 on its fifth. The song also debuted at No. 7 on the Hungarian Singles Chart.

Stiff Little Fingers Covered the song as part of their Silly Encores B-Side and also appeared on their USA release album - Hanx!.

Boy George did make a cover of the song in 2009 and released as a single in digital download format.