Which Blondie song from Parallel Lines topped the US and UK singles charts in 1979?

The Blondie song from Parallel Lines that topped both the US and UK singles charts in 1979 was “Heart of Glass.”

Written by Debbie Harry and Chris Stein, the song began as an earlier, slower composition called “Once I Had a Love.” Producer Mike Chapman helped the band reshape it into a sleek disco-influenced track, combining Blondie’s New York new-wave identity with synthesizers, a steady dance beat, and electronic textures.

“Heart of Glass” was released as Parallel Lines’ third single in January 1979 after an earlier 12-inch version appeared in December 1978. It became Blondie’s first US Billboard Hot 100 number-one hit and also reached number one on the UK Singles Chart. The success transformed the band from a celebrated New York underground act into international pop stars.

A common mix-up is “Call Me,” another Blondie chart-topper. However, “Call Me” was recorded for the 1980 film American Gigolo and was not a Parallel Lines track. “Dreaming” and “Atomic” were also successful Blondie singles, but neither topped both charts in 1979.