"Johnny and Mary" went to no. 44 on the UK Singles Chart, and was a top 40 hit in Canada, Australia, New Zealand, South Africa and several European countries. In Germany, it peaked at no. 7 on the singles chart and spent a total of 23 weeks in the Top 20. In Spain, it peaked at no. 1 on the Spanish singles chart (AFYVE).
Though the single did not chart in the US Hot 100, it did reach no. 18 on Billboard's Club Play Singles chart.
"Johnny and Mary" was used as the signature tune in advertisements promoting Renault cars throughout the 1980s and 1990s. Early adverts used Palmer's original version, while a range of special recordings in different styles were produced during the 1990s, most famously an acoustic interpretation by Martin Taylor, which he released on his album Spirit of Django. Taylor recorded alternate versions for Renault; the last being in 1998 for the launch of the all-new Renault Clio.
French band Nouvelle Vague recorded their version with a Polish singer Ania on the Polish edition of their 2009 album 3. The song was also included on the deluxe edition of Ania's 2010 album Ania Movie.