Sienna Miller oozes sophistication in denim midi dress and leather trench coat - her unique lace up boots complement the look beautifully

We love Sienna Miller's gorgeously flattering and versatile denim midi dress that's sure to become an autumn staple this season - her vampy styling with a leather trench coat and matching lace up boots was a stroke of genius.

Sienna Miller is a huge fan of denim and regularly steps out in impossibly cool denim styles, like barrel leg jeans and ultra-baggy styles, to give us the best casual-chic outfit inspiration out there.

But while we will always love a flattering pair of denim jeans, this season we're moving on and denim midi dresses are the staple we're adding to our autumn capsule wardrobes thanks to the celebrity.

Sienna looked simply stunning when she stepped out in London this week wearing an A-line denim midi dress, with a fitted bodice, flattering square neckline and flowing skirt. The deep indigo hue was so striking yet with it being denim, a fabric we know and love, the style felt incredibly wearable.

The dress itself was simple, with no embellishments or unique silhouette. Its beauty lied instead in the impeccable and flattering fit. Sienna let this shine with her pared back styling too, adding a simple gold chain link necklace and a matching gold bracelet.

To keep warm in the cool autumn weather, she paired the dress with a vampy leather trench coat. We love this edgy take on how to style a trench coat, with the heavy material beautifully complementing the rich denim of her dress and adding some more texture into her look.

She finished off the look with a matching pair of leather boots. The point-toe, lace-up boots are so chic, with a very subtle crocodile print adorning the leather to give an elevated and vintage feel to the footwear.

Shop Sienna Miller's Look

While Sienna deviated from her usual boho style with this effortless and laid-back take on eveningwear, she couldn't leave behind her iconic long waves. Styling her hair in her usual middle parting, her healthy and glowing blonde strands cascaded around her face, with lots of volume at the roots creating a lovely flowing style.

For makeup, she kept her style ultra-natural, with a bold brow bringing dimension to her face while a natural nude lipstick shade added a subtle pop of pink to the look.

We love this pared back and simple look, with each element, from the footwear to the lipstick, working together to create a cohesive, wearable and fun style that we can't wait to recreate.