NB Bancorp, Inc.

NBBK·NASDAQ·$20.24Share Price as of 11/2·$840MMarket Cap as of 11/2

Financials

10-QQ2 ended 06/30/2608/07/26 10-QQ1 ended 03/31/2605/08/26 10-KFY 202503/03/26 10-QQ3 ended 09/30/2511/07/25 10-QQ2 ended 06/30/2508/08/25

Disclosures

8-KCurrent report10/15/26 8-KCurrent report07/22/26 8-KCurrent report05/21/26 8-KCurrent report05/13/26 8-KCurrent report04/29/26

Prospectuses and Registrations

S-8 POSPost-effective amendment (S-8)02/09/26 S-8Registration of securities for employees11/14/25 424B3Prospectus07/30/25 S-4/ARegistration (business combination, amended)07/28/25 S-4Registration (business combination)07/02/25

Proxies

DEF 14ADefinitive proxy03/27/26 DEF 14ADefinitive proxy03/14/25 DEF 14ADefinitive proxy04/12/24 DEFA14AAdditional proxy materials04/12/24

Ownership

Form 4Insider transaction08/21/26 Form 4Insider transaction08/21/26 Form 4Insider transaction08/18/26 Form 4Insider transaction05/18/26 4/AInsider transaction (amended)05/15/26

Other

11-KEmployee stock purchase plan report06/25/26 ARSAnnual report to shareholders03/27/26 42542511/13/25 42542511/13/25 42542510/31/25