"Fidelity" is a song by American singer-songwriter Regina Spektor, released as the second single from her fourth album Begin to Hope. The song marked Spektor's first and only Billboard 100 entry and is her most successful track to date. Despite a release date of September 25 (its popular music video was released even earlier), the song did not hit the charts until December. The song was released in the UK as a two-part single on March 12, 2007. The song makes it Spektor's highest-charting single across the world.