Solo and offline are different labels
NBA 2K27’s Steam listing explicitly names Play Now, MyNBA and The W as available offline. It states that the remaining modes and features need an internet connection. A single-player activity inside an online mode does not escape that requirement merely because the opponent is controlled by AI.
This matters especially for MyTEAM challenges and a personal MyCAREER save. Their solo presentation should not be interpreted as a guarantee that they remain accessible without the service.
Prepare a disconnected session before travel
Install and start the game while connected. Complete Steam authentication and the required first-run software setup. Then open the exact mode you intend to use and confirm that an appropriate save is available.
If you expect to play without a reliable connection, test that arrangement at home before relying on it. A mode label does not describe every optional roster download or other connected feature surrounding the mode.
Choose according to your goal
Use Play Now for a direct basketball session, MyNBA for a franchise-focused plan, or The W for its career experience. The official mode breakdown is useful for understanding the larger menu, but the store’s explicit offline statement controls this connectivity answer.
Do not purchase VC or a premium pass expecting those items to remove an internet requirement. Buying extra content and obtaining offline access are separate questions.