The 31-year-old actress was seen supporting her hubby at the premiere of his latest film, Runner Runner, in Las Vegas yesterday (18 September) and decided to switch up her style for the occasion.
Proving that red carpets don't always call for an overly glamorous gown, Jessica stepped out in a chic double breasted jacket, a crisp white shirt and tailored black trousers.
The jacket was off-set with white buttons and satin lapels and appeared extremely figure flattering, as it drew attention to Jessica's waist while creating the illusion of curves, too.
She completed her outfit with a box-shaped handbag and a pair of elegant Giambattista Valli heels.
Jessica also kept her make-up and hair simple, tying her brown locks back into a cute bun.
However, although her hair 'do might seem low-key, it looks like it took some serious work to create.
Posting a picture on Instagram of her hair stylist at work, Jessica demonstrated how her go-to-guy delivers the ultimate bun - by getting her to hold her head upside down! So we won't be trying this one at home then.
Meanwhile, Justin - who married Jessica in Italy last October - also got suited up for the evening in a navy blue jacket with similar satin lapels to his wife's and a pair of matching trousers.
What a cute couple they make!
What do you think of Jessica's smart ensemble? Let us know below, as the best comment each week wins £50!