SanDisk 256GB microSDXC UHS-I Memory Card for Nintendo Switch SDSQXAO-256G-ANCZN - Best Buy
400 GB is no longer the biggest microSD card available. As of some time in February 2018, there will be a (very likely expensive!) 512 GB microSD card on the market! : r/gpdwin
Best microSD cards of 2023: Speed, capacity, cost compared | ZDNET
Amazon.com: SanDisk Ultra 1TB Micro SD Card Works with Nintendo Switch & Nintendo Switch Lite Console (SDSQUA4-1T00-GN6MN) UHS-1 Class 10 Bundle with (1) Everything But Stromboli SD & MicroSD Memory Card Reader :