Fellow The Saturdays Mollie King, Rochelle Wiseman and Vanessa White popped on their party dresses before slipping a 'bride to be' sash on gorgeous 25-year-old Frankie!
Along with what looks like a tiara and the obligatory bridal garter, Ms Sandford, resplendent in a red dress, was ready to go!
Mollie still can't believe that her bestie is getting married to footballer Wayne Bridge later in July, and accompanied her snaps from the night with: "Frankie's hen! Can't believe she's getting MARRIED."
Soon enough, the girls were making the most of the drinks available at their sumptuous venue, even enjoying champagne ice pops at one point.
Now they sound delicious!
Frankie had already partied up a storm on her first hen do in Ibiza, but who can blame a girl for wanting another girls-only bash? Not us!
Party gal Vanessa, looking lovely in a yellow lace dress, even posed with an entire bottle of vodka. Atta girl!
She also found an unsuspecting gent who was catching forty winks near by, and posed for a snap with him. She added: "Don't fall asleep next to a hen party…."
Sage advice, Vanessa!
Frankie's friend Sarah was with the girls for the hen do at Henley (find out which other stars have been partying at the posh event here) and posted some snaps on her Instagram page, adding: "Bride to be."
We couldn't see pics of Una Healy with the girls, but on 1 July she Tweeted: "Tonsilitis." Ouch, hope you're feeling better soon Una.
It looks like Frankie had an amazing night though. Roll on wedding day!
Obsessed with weddings? You can read our girl Hannah's wedding blog here.
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