Sienna Miller’s Messy Bun Is Summer Hair Goals

When it comes to summer hair, low effort with high impact is always the goal. Sienna Miller just reminded us why the messy bun is a warm-weather essential. At Wimbledon, the actress stepped out with an effortlessly chic updo that felt casual yet refined, proving once again that messy doesn’t mean unkempt. Her loosely styled bun gave off a breezy, lived-in vibe that’s ideal for hot summer days when you want your hair up and out of the way without sacrificing style.

“It’s got that thrown-it-up-myself feel,” says Hersheson, noting how the look strikes the perfect balance between relaxed and elevated. With softly pulled-back strands, face-framing tendrils, and a bit of volume at the crown, the style flatters from every angle whether you’re poolside, brunching, or in the middle of a busy summer workday.

The messy bun isn’t a new concept, but Sienna’s spin gives it fresh 2025 relevance. It’s a perfect match for summer’s easygoing energy and, best of all, it works with just about any hair type. Ahead, find tips for achieving the look and making it your go-to summer hairstyle.

The OG version: slightly tousled, mid-height bun with subtle volume. It’s the ultimate “didn’t try, but look amazing” energy just like Sienna’s off-duty red carpet looks.