The sad news was confirmed on Sunday (2 August) by Spanish police.
A spokesperson said: "I can confirm the death of British national Priscilla White, aged 72.
"We are still awaiting autopsy results but everything at this stage is pointing towards her death being the result of natural causes."
TV entertainer Cilla was known for her singing career in the 60s, and for becoming one of TV's most loved presenters on shows such as Blind Date and Surprise Surprise.
At the time of her death, she was living a life of semi-retirement at her home in Estepona on the Costa del Sol, Spain. She reportedly suffered from hearing problems and arthritis.
Tributes have been pouring in via Twitter for the Liverpudlian TV legend.
Holly Willoughby tweeted: "So so sad to hear the news that we have lost one of my heroes, Cilla you were one incredible lady! Sending all my love to her family. X"
This photo is even more special to me now... pic.twitter.com/nmUcArmJjO— Holly Willoughby (@hollywills) August 2, 2015
Phillip Schofield added: "I've just heard the incredibly sad news that the legendary Cilla has died. So sad. A truly wonderful lady and an entertainment icon."
Blue singer Antony Costa wrote: "Such sad news about cilla black she was such a lovely person..I met her so many times she surprised me at the age 14 for surprise surprise x."
Former TOWIE star Charlie King wrote: "Truly gutted to hear about Cilla Black passing away. Truly a legend of music and TV. A sad day indeed."
Host and DJ Mark Wright said: "Rip Cilla Black !! Shocking news !! Amazing women. Loved her shows growing up too !! Xx."
TV presenter Gabby Logan said: "Cilla Black was the complete entertainer/host in an era when everyone watched TV. She was a trail blazer. RIP Cilla."
So sad to hear that Cilla Black has passed away, she will always be a legend and I was truly lucky to have met her x pic.twitter.com/uXqCWEa8KH— Harry Derbidge (@MrHarryDerbidge) August 2, 2015
CBB star Casey Batchelor added to the throng of mourners when she tweeted: "Wow!!! R.I.P Miss Cilla Black......a showbiz legend!!"
Reality star Maria Fowler added: "Oh my gosh, rest in peace Cilla black. A true entertainment legend."
Eamonn Holmes lamented: "Another passing of a Legend. #RIPCilla Always loved being in her company. Condolences to Robert and Family. She was a National Treasure."
Cilla leaves behind three sons, Robert, Ben and Jack, as well as two grandchildren.
She was married for 30 years to her manager Bobby Willis until he died in 1999 of lung cancer, aged just 57.
The national treasure said she was 'over the moon' when she received an outstanding contribution prize at the BAFTA Television Awards in 2014.
Sheridan Smith recently played the entertainer in the three-part ITV drama Cilla.
On hearing the sad news of Cilla's death, Sheridan said: "I'm absolutely devastated to hear the tragic news about Cilla. She was the most remarkable woman, a true legend.
"She was so kind and helpful to me, it was a privilege to play her. My condolences go out to her family and all who loved her. She will be truly missed."
Rest in peace Cilla... Or should we say "ta-ra chuck"!
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