I'd define a "recurring" character as someone who appeared on at least two episodes (not including the finale), but no more than 15. This would eliminate characters like Newman, Mr./Mrs. Seinfeld, the Costanzas, J. Peterman, Susan, etc., who I think were featured too often to be considered "recurring".
Here's my top 10:
1. Puddy
2. Bania
3. Mickey Abbott
4. Jackie Chiles
5. Crazy Joe Davola
6. Mr. Pitt
7. Kruger
8. Babu Bhatt
9. Jack Klompus
10. Uncle Leo
Honorary Citation of Achievement to Mr. Bookman, best single episode appearance with the Soup Nazi a close second.
Curious to hear from other Seinfeld aficionados on this.
Here's my top 10:
1. Puddy
2. Bania
3. Mickey Abbott
4. Jackie Chiles
5. Crazy Joe Davola
6. Mr. Pitt
7. Kruger
8. Babu Bhatt
9. Jack Klompus
10. Uncle Leo
Honorary Citation of Achievement to Mr. Bookman, best single episode appearance with the Soup Nazi a close second.
Curious to hear from other Seinfeld aficionados on this.