* 今度 (kondo): This is a general and common way to say "next time." It's relatively neutral in formality.
* 次回 (jikai): This is a more formal way to say "next time," often used in written communication or announcements.
* また (mata): This means "again" or "next time," and is very common in spoken Japanese. It's less specific than "kondo" and can be used to refer to a future unspecified occasion. You'll often hear it as "Mata ne!" (See you again!)
The best option depends on the situation. For most casual conversations, `今度 (kondo)` or `また (mata)` would be appropriate. For formal situations, `次回 (jikai)` is preferred.