The pair were inseparable at Glastonbury Festival last week but it was back to work as usual today.
The former Made In Chelsea star wasn't going to let the sheets of city rain dictate her outfit choice or stop her from glamming up and heading out - oh no.
The stunner proved her fashion credentials (and then some) and slipped into this incredibly gorgeous monochrome number by Amanda Wakeley that boasted a jet-black sash, matching chunky straps and a distressed midi skirt.
Puddles weren't on Ms. Mackintosh's mind when she chose her shoes this morning and the reality star turned fashion designer ditched the courts and safe pixie boots for a pair of barely there, Kim Kardashian-inspired sandals to match her fabulous frock.
Millie - who embraced festival beauty at muddy Glasto with face jewels and a whole 'loada glitter - decided on the natural vibes today. A swipe of pretty pink lippie and a dusting of warm bronzer was all she needed to complete her lovely look.
Can we also just take a moment to marvel over her amazing tan? Gah, she's got it all.
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