Kudos to Kate for being just like the rest of us and digging her favourite white E+O ski jacket, first seen on the slopes back in 2008, out of the cupboard for her recent family ski trip to Courchevel. She’s clearly a fan of its flattering cut, understated but cosy faux fur collar and discreet branding – in contrast to the obvious spider branding, on William’s Spyder jacket. Maybe she also likes it because no one will be able to get one the same.

E+O was a brand set up in 2007 by Paul Goldstein, a British skiwear entrepreneur who founded the Nevica brand and designed and manufactured the classily expensive Killy brand under licence between 1992 and 2006. E+O was designed to compete with Killy, albeit at a lower price, focusing on flattering cuts for both men and women, comfort and clever details.

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E+O (which was said to stand for, among other things, English + Outspoken) had quality on its side, and got itself noticed by dressing Ski Sunday presenter Graham Bell as well as the royals. But in the end, unable to compete with better-known brands, Goldstein sold out to a East Asian buyer in 2010, and E+O skiwear is now effectively defunct.

So where should Kate – and the numerous admirers seeking to imitate her style – go for a new, similar jacket?

Brands with a similar vision to E+O and Killy – high end but still targeting skiers who mean to ski not just sit on restaurant terraces – include Spyder, Kjus and Schöffel. All make jackets with prices upwards of £500 (Spyder has a women’s jacket with faux fur collar, appropriately called Posh, for £650), and focus on cut and styling designed to flatter. Pocket and colour panel positioning, subtly padded shoulders, stretch materials and low-profile side panels are just a few of the tricks.

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But it’s not just about the look – their water resistance and breathability also tends to be top notch. The materials the jackets are made of look, feel and are expensive, including top quality faux fur that looks almost real for example, plus there tend to be more thoughtful details – such as a removable, washable make-up collar – than on similar looking cheaper brands.

Slightly less expensive but still high on both style and function are Eider and Salomon. While a £170 Dare 2b ski jacket may be a near match for the look of Kate’s – the brand does a great job of luxe styling at a lower price – feel, fit and weatherproofing will not be the same.

Telegraph Ski’s review of the best jackets for 2016 includes the men’s Schöffel Josh, £490, and women’s Eider Sun Peak, £380. Check out the latest fashion for the season (beyond Kate white…) in our trends feature. Go on Mrs Windsor, you know you want to.