Ahead of her stylish appearance, the account shared nine of the royal's greatest fashion hits in years gone by.
The earliest choice was a powder blue coat worn by the-then teenage princess with knee-high boots and a roll-neck - an ensemble which makes us wish winter would hurry up already.
It was certainly a fashionable period for the princess, as two outfits from 1969 were also shared via Instagram Stories.
For Prince Charles' investiture of Prince Charles as Prince of Wales at Caernarvon Castle - an event well-documented on The Crown - the royal chose a peacock blue coat dress and matching hat.
A teensy handbag and matching ladylike gloves completed the ensemble.
While a sunshine yellow ensemble proved she inherited the Queen's unflinching love for colour.
A third image further demonstrates the royal's knack for trend forecasting too, as the 69-year-old was working tonal hues back in 2009 - a decade before we trialled the look.
But Princess Anne's fashionable influence wasn't left on the sidelines, as the runway boasted regal references this season too.
Over at Shrimps, British designer Hannah Weiland proved she'd done her homework admitting that if she could dress anyone it would be the Queen.
The line was sprinkled with references to her daughter's closet too with models stepping out in jodhpurs, shouldn't-be-cool-but-work sports sunglasses and heavy faux fur coats.
Long live Princess Anne's wardrobe, tights and all!