Fashion's biggest night anchors to one calendar rule. Why is the Met Gala always the first Monday in May ties the Costume Institute benefit to spring exhibition openings and a museum closure the public plans around yearly.

Each gala introduces a blockbuster Costume Institute show — 2026's Costume Art is the latest. Why is the Met Gala always the first Monday in May makes the fundraiser the champagne preview before ticketed visitors enter the galleries.

The Met closes to the public that Monday while crews convert galleries into a great hall. Why is the Met Gala always the first Monday in May lets NYPD, caterers, and conservation staff book the same closure window annually.

The gala moved dates for decades after 1948. Why is the Met Gala always the first Monday in May became firm in 2005 with the Chanel exhibition — though May spring openings started with Jacqueline Kennedy in 2001.

Red carpet arrivals roll into a seated fundraiser upstairs. Why is the Met Gala always the first Monday in May gives Vogue a predictable live broadcast slot and donors a timed exhibition walk-through.