To promote the theatrical release of X-MEN: DARK PHOENIX, 20th Century Fox partnered with pop culture retailer BoxLunch.

The partnership consisted of a line of branded content being sold by BoxLunch. The branded collection included branded T-shirts, socks, hats and more.

The partnership was further promoted by the X-Men Super Fan Social Sweepstakes. The Sweepstakes, shared by BoxLunch on Twitter, gave a grand prize winner a prize pack that included a signed DARK PHOENIX poster, an X-Men: Apocolypse Magneto helmet, an X-Men T-shirt and a BoxLunch gift card.

Two runner-up winners received a signed DARK PHOENIX poster and a Cyclops visor.

Fans entered online by following @XMenMovies on Twitter and using the hashtags #XMenDay, #DarkPhoenix and #Sweepstakes in their entry post. The winner was selected randomly on May 18, 2019.