There is just a week to go before she watches her sister walk up the aisle.
And chief bridesmaid Princess Beatrice looked to be in high spirits as she enjoyed a night on the town last night.
The Duke of York’s eldest daughter, 30, was spotted leaving Mayfair private members’ club George at 2.30am on Friday morning before climbing into a waiting vehicle.
Dressed in a £2,050 midnight blue Mary Katrantzou frock, the Queen’s granddaughter accessorised with a £995 fringed jacket from Galvan, a black clutch and pointed heels.
The VIP visitor wore her hair in loose curls which were brushed back into a loose side parting, keeping her makeup to a minimum.
It is not known whether Beatrice is a member of the exclusive club – which counts the likes of David Cameron among its regulars and costs more than £750 a year – or just a guest.
Infamous for its strict dress code, t-shirts, leggings and flip flops are strictly banned for female guests while men are forbidden from sporting untucked shirts.
A bottle of wine can cost as much as £28 a glass, while one bottle of vintage champagne is priced at an eye-watering £700.
Beatrice is thought to be staying at her London base in St. James’s Palace, just a stone’s throw from Mayfair, ahead of her sister’s big day.
The royal, who works for business management consultancy Afiniti, splits her time between London, Windsor and New York.
She recently spoke about the trials and tribulations of life as a princess, telling British Vogue: ‘It’s hard to navigate situations like these because there is no precedent, there is no protocol.
‘We are the first: we are young women trying to build careers and have personal lives, and we’re also princesses, and doing all of this in the public eye.’
Eugenie will walk down the aisle at St. George’s Chapel, Windsor Castle on Friday 12th October to exchange vows with her long-term partner Jack Brooksbank.
The official line up of bridesmaids and pageboys has yet to be announced, but Prince George and Princess Charlotte are tipped to play a role.
Robbie Williams daughter Teddy is also rumoured to be one of the bridesmaids after Eugenie struck up a friendship with the singer and his wife Ayda Field.
It is thought that Eugenie has also invited a string of celebrities including George and Amal Clooney, singer Ellie Goulding and model Cara Delevingne.