Can You Disable Chat on Xbox Live? Not Fully, But You Can Limit It

You can't fully disable chat, but you can limit it:

Mute Individual Players

1. In game/party: Press Xbox button → highlight player → Menu button → Mute

Restrict Chat Features via Privacy Settings

1. Xbox button → Profile & system → Settings → Account → Privacy & online safety
2. Adjust: Block party chat, game chat, messages

Note: Only way to avoid chat entirely is not joining online games/parties. Report harassment via Xbox Guide.