Sir Cliff Richard will sing at the Mass at St Mary's RC Church in Woolton and TV stars Paul O'Grady, Jimmy Tarbuck and Christopher Biggins will join her sons Robert and Ben in giving readings.
In Cilla's home city of Liverpool a book of condolence has been signed by 3,000.
Cilla would probably not have wanted a 'lorra, lorra fuss' and she will be laid to rest at a private ceremony in Allerton Cemetery, where her parents are buried.
But ahead of that Thursday there will be a funeral service at St Mary's Church in the suburb of Woolton and fans young and old, plus more than a smattering of celebrities will no doubt be out in force.
The funeral cortege will start at the junction of Woolton Road and Church Road North, and will travel to the junction with Blackwood Avenue before continuing to the church.
Cilla married Bobby Willis at a London registry office in January 1969 but two months later they married in St Mary's Church following a dispensation to marry and pleasing Cilla's family.
Cilla died August 1, during extreme hot temperatures in Spain. She fell and suffered a stroke.
Since her passing many in the media have noted that she had already talked about dying putting a 'good time to go' as around age 75.
In recent years Cilla's hearing was failing and arthritis was a constant reminder of the passing of time. Cilla had said she did not want to continue onto great old age with bits falling off here and there.
Then there was the loss of her husband Bobby which had taken its toll; her beloved husband Bobby Willis died in 1999 and was cremated.
BBC News reports "The late entertainer's representative said further details would be released "once all the preparations have been finalised". A statement said: "Once again the family have asked for their privacy to be continually respected at this difficult time"."
To be fair the media seems to have been respecting their privacy since she died August 1.
Cilla was a hugely popular entertainer, her career spanning at least five decades. Fans were shocked at news of her sudden passing. Her three sons are still coming to term with their loss.
But Cilla's friends, family and colleagues are determined to give her a great send off and Liverpool is expected to come to a standstill for at least part of Thursday.
Cilla's funeral - Ta-ra Cilla
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