From St Pancras International, Thameslink trains run directly to Gatwick through central London

https://lorenzoobxe263.yousher.com/gatwick-airport-travel-times-what-to-expect-from-different-routes-1

From St Pancras International, Thameslink trains run directly to Gatwick through central London. It’s ideal if you’re arriving by Eurostar or connecting from the Midlands.