Fashion matters at Marks & Spencer. Clothes are an emotional purchase, and when M&S is successfully delivering clothes that its customers desire, it’s a strong sign that the retailer is on the right wavelength. Food may be a much larger part of the business these days but fashion is the bellwether.

The strong sales figures for the past year that M&S revealed on Wednesday have been driven not just by the below-the-radar basics of underwear and T-shirts but in the fashion-forward categories of denim and dresses.

The Sienna straight-leg jeans with stretch, which sell for £22.50, are a current bestseller and illustrate how the store is finding the confidence to deliver denim that speaks to contemporary style without pitching too far into faddish trends. The Sienna jeans sit just below the natural waist and are fitted through the hips, but release from just above the knee to the ankle, for a silhouette that looks more up-to-date than a skinny jean without being challenging to wear. Sizing is inclusive (6-24) and well thought through (jeans and trousers come in five lengths).

Some of the best day dresses on the high street right now are to be found on the M&S shopfloor. The floral Midaxi tea dress takes the simple high neckline, fitted bodice and sleeves cropped with a soft flounce at the elbow that is the signature silhouette of the Vampire’s Wife Falconetti dress, beloved of high-profile women from the Princess of Wales to the actor Rachel Weisz, and gives it an everywoman spin in a ditsy floral print. Meanwhile the linen-rich button-through midi dress, in earthy shades of terracotta or deep green, could tempt a few minimalist Cos shoppers to experiment with M&S. Both of these dresses are £39.50, which M&S has identified as a pricing sweet spot: expensive enough not to present as a throwaway, impulse purchase, without being prohibitive.

The demise of Gap and Topshop has given M&S an opportunity to win consumers who are interested in fashion, but who are more comfortable shopping with an established brand than from the small, Instagram-driven labels that now dress many online-only Generation-Z shoppers. The growing trend for brands to charge for returns is making shoppers value stores where sizing is reliable. The assurance that size 12 garments across the shopfloor will fit the same measurements – not at all a given at many high street stores – is the kind of non-glamorous but eminently sensible advantage of M&S that is proving a winner.

Another part of this story is luck. The style zeitgeist has moved in an M&S-friendly direction. After several successive catwalk seasons in which trench coats, shirting and well-cut trousers have been the standout hits of Milan and Paris fashion weeks, it is clear that fashion has shifted away from a carousel of quickfire trends and settled into a groove of timeless classics and understated separates. Linen, a classic fabric that has always been an M&S staple, is fashionable again. (Cate Blanchett even wore a linen shirt and matching floor-length skirt on the red carpet, at the Critic’s Choice awards earlier this year.)

There is still a perception gap for M&S to traverse. When I complimented a fashion industry friend recently on her ruched-sleeve oatmeal linen blazer, she showed me the M&S label with a “who knew?” raised eyebrow. It is currently available for £59. I wouldn’t bet against it selling out.

By Jess Cartner-Morley