Millie Bobby Brown created a 22-piece collection with Vogue Eyewear in 2021, emphasizing personal style and self-expression. Millie Bobby Brown expressed that style is personal to her, and the collection goes beyond just shielding her from paparazzi.

Millie Bobby Brown became the face of Pandora in 2019 for their Pandora Me collection, which focuses on customizable jewelry designed for a younger demographic.

Millie Bobby Brown teamed up with Crocs for their all-new Unfurgettable Clog campaign, featuring a whimsical tea party-inspired setting alongside her dog, and lensed by Lillie Eiger.

Millie Bobby Brown founded Florence by Mills in 2019, focusing on clean beauty products designed for young skin. The brand's name honors her great-grandmother, reflecting values of individuality and bravery that inspire its creation.