The UK's Official Singles Chart is entering a new era, with video counting towards the weekly rundown for the first time, the Official Charts Company has said.
Streaming and downloading of videos from artists will count towards the UK's only official singles countdown, which is compiled by the Official Charts Company and unveiled by BBC Radio 1 every Friday afternoon.
The change, developed in conjunction with the British music industry and digital platforms, comes as established audio services such as Apple Music and Spotify add video to their offer and YouTube prepare to launch their first subscription service, signalling a key moment in the development of the premium music video sector.
The change is designed to ensure the chart remains a showcase for hit music, however music fans choose to access it.
The Official Singles Chart will continue to be the only official countdown in the UK market, reflecting sales of downloads, CD and vinyl, as well as streams of audio tracks or video tracks, whether on premium subscription or ad-funded services.
The services which will contribute video streams will include Apple Music, Spotify, YouTube and Tidal.
The change will be effective from the chart published on July 6.
Official Charts Company chief executive Martin Talbot said: "This is a significant step for the UK and ensures The Official Chart (which is unveiled exclusively on BBC Radio 1) continues to be the most comprehensive and trusted chart in the UK, bar none.
"Consumption of recorded music via more than 15,000 retailers, download stores and streaming services of all kinds contribute to the weekly chart countdown.
"In the modern era, artists are increasingly multi-faceted creators, with a highly developed visual sense running in parallel with their music.
"The addition of video ensures that the Official Singles Chart reflects the creativity of the artist in the broadest way possible - and music fans' engagement with that vision."
In a parallel change, free ad-funded streams will be weighted at a different rate in the UK's Official Singles Chart compared with streams played under a paid-for subscription from the July 6 chart.
One hundred streams via a subscription service will equate to one sale, as will 600 "free" streams. This replaces the current combined conversion rate, which means all streams are treated equally - with one sale equivalent to 150 streams.
It will apply to both video and audio streams equally.
The Official Charts conversion rates have been agreed following consultation across the industry and will be subject to review.