Do US Nintendo DS Games Work on UK Consoles? Yes (With Caveats)

Yes. Original Nintendo DS, DS Lite, and DSi are region-free for DS game cards. A US cartridge plays on a UK console (and vice versa).

Caveats

• DSi-enhanced / DSi-exclusive titles (e.g., Pokémon Black/White have DSi features) are region-locked on DSi/3DS – a US DSi cart won't work on a UK DSi/3DS in DSi mode. On original DS/DS Lite they run in DS mode and work fine.
• Online multiplayer may connect to region-specific servers; some games restrict cross-region matchmaking.
• Language: Game text follows cartridge region (usually English for US).

For standard DS games on DS/DS Lite: fully compatible.