United Airlines maintains some of the strictest access rules for its Polaris Lounges to ensure they remain exclusive and uncrowded. To enter, you must be traveling on a same-day international flight in United Polaris business class. This specifically excludes domestic first class, United First to Canada or Mexico, and even "Premium Plus" (Premium Economy) passengers. You can also gain access if you are flying in long-haul international First or Business class on a Star Alliance partner airline (like Lufthansa or ANA), but only from the specific airport where your long-haul flight departs. Unlike standard United Clubs, you cannot enter based on Star Alliance Gold status alone, nor can you buy a day pass or use a credit card "one-time pass." There are generally no guests allowed for Polaris business class passengers, though international First Class passengers on Star Alliance partners may typically bring one guest. The rules are designed to protect the "quiet luxury" environment, which includes sit-down dining, shower suites, and nap pods.