She is preparing for her imminent wedding to record producer fiancé David Foster.
And Katharine McPhee was having fun sightseeing with family and close friends around London on Thursday ahead of the big day.
The actress and singer, 35, wore a stunning full-length lace shirt dress as she and her husband-to-be, 69, were joined by her mother Peisha and sister Adriana as they enjoyed the sights of the city from an open top bus.
Wedding bells: Katharine McPhee was having fun sightseeing with family and close friends around London on Thursday ahead of her wedding this weekend
The American Idol star looked sensational in the white ensemble, wearing her honey-coloured locks in loose curls.
The West End favourite wore natural make-up while joining her nearest and dearest for the fun-filled outing.
The group, which included American Idol vocal coach Michael Orland, then headed to a bar to continue the celebrations.
Her friends took plenty of Instagram stories, with vocal coach Michael sharing a sweet tribute to Katharine’s beau, admitting he was there the first time they met.
Family time: The actress and singer, 35, wore a stunning full-length lace shirt dress as she and her husband-to-be, 69, were joined by her mother Peisha and sister Adriana
Having a ball: The American Idol star looked sensational in the white ensemble, wearing her honey-coloured locks in loose curls
He wrote: ‘I was at the piano when @davidfoster and @katharinemcphee and I’m always proud to call him my friend. #Over11yearsAgo’.
The celebration comes just before her big wedding day.
DailyMail.com has learned the nuptials are expected to take place in London this weekend and will be a small, intimate celebration with around 80 guests.
‘It won’t be a big showbiz wedding like his previous nuptials. This one is more focused on their respective families and very close friends,’ said an insider.
Fantastic: The group, which included vocal coach Michael Orland, then headed to a bar to continue the celebrations
Sweet: Vocal coach Michael shared a sweet tribute to Katharine’s beau, admitting he was there the first time they met over 11 years ago on American Idol
Katharine has been gallivanting across London with her loved ones, including a family dinner on Wednesday evening.
As shown on her Instagram stories, Katharine treated guests to a song and joined the waiting staff at their meal for a medley of pop tunes.
Katharine shared that ‘things took an interesting turn when the waitress burst into song,’ over a clip of two of the staff serenading David.
Her cousin Daniel Corbett got up and joined in the fun as the waiters and waitresses belted out a rendition of the 1977 David Bowie song Heroes.
So happy: Katharine and David were first linked in May 2017, and confirmed their engagement in June 2018 after he popped the question on the Italian island of Capri (pictured in March)
‘Then I took it to the next level and started to really scare my new family,’ Katharine wrote on a video of her singing and dancing with the staff.
By that point, the group had broken into the 1968 song Proud Mary originated by Creedence Clearwater Revival and also memorably sung by Ike and Tina Turner.
David’s daughters Sara, 38, and Erin Foster, 36 – whom he had with former model ex-wife Rebecca Dyer – are already in London as their recent Instagram posts showed them at the Dorchester Hotel.
Only the best: Katharine treated guests to a song and joined the waiting staff at their meal for a medley of pop tunes on Wednesday night
The couple picked up their marriage licence in Beverly Hills in mid May, and it expires 90 days after it was taken out.
Katharine has been enjoying a string of festivities ahead of her wedding to David, including a romantic getaway to Mykonos.
The former Waitress star married to actor Nick Cokas, 54, in February 2008 after three years together.
Katharine was seen kissing her married Smash director Michael Morris while she was still with her husband in October 2013.
She filed for divorce in May 2014, with her spokesperson confirming the couple had quietly separated a year previously after four years of marriage.
In a great mood: Katharine has been enjoying a string of festivities ahead of her wedding to David, including a romantic getaway to Mykonos
Katherine then dated her Scorpion co-star Elyes Gabel, 36, for two years.
She and David were first linked in May 2017, and confirmed their engagement in June 2018 after the producer popped the question on the Italian island of Capri.
David has been married four times and has five daughters and seven grandchildren.
He was first married in 1972 to singer B.J Cook and the couple had one daughter, Amy, before divorcing after just under 10 years of marriage.
David married his second wife Rebecca Dyer in 1982 and they had three daughters, Sara, Erin and Jordan. They ended their marriage after four years in 1986.
Moving onto his third marriage, the record mogul wed actress Linda Thompson in 1991 and they collaborated on songs together throughout their marriage – but ended things in 2005.
During this marriage, David was step-father to Linda’s sons with Caitlyn Jenner, Brody and Brandon, who grew up living in his home in Malibu.
Upon David’s fourth marriage, he wed Dutch model Yolanda Hadid – mother to stunning supermodel sisters Gigi and Bella Hadid.
After a nine year relationship and four years of marriage, David and the Real Housewives of Beverley Hills star called things quits in 2015.
David had his first daughter, Allison, when he was just 20 and was forced to put her up for adoption before the pair reconciled when she was 30.
Wedding vibes: Katharine has been gallivanting across London with her loved ones in the lead up to the big day
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