v3.26.1
Document and Entity Information - USD ($)
12 Months Ended
Dec. 31, 2025
Mar. 25, 2026
Jun. 30, 2025
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Transition Report false    
Document Period End Date Dec. 31, 2025    
Entity Central Index Key 0002058758    
Current Fiscal Year End Date --12-31    
Document Fiscal Year Focus 2025    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity File Number 001-42775    
Entity Registrant Name Avidia Bancorp, Inc.    
Entity Incorporation, State or Country Code MD    
Entity Tax Identification Number 33-4239888    
Entity Address, Address Line One 42 Main Street    
Entity Address, City or Town Hudson    
Entity Address, State or Province MA    
Entity Address, Postal Zip Code 01749    
City Area Code 800    
Local Phone Number 508-2265    
Title of 12(b) Security Common stock, $0.01 par value    
Trading Symbol AVBC    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company true    
Entity Ex Transition Period false    
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Public Float     $ 0
Entity Common Stock, Shares Outstanding   20,076,250  
Auditor Firm ID 7293    
Auditor Name BDMP Assurance, LLP    
Auditor Location Portland, Maine    
Auditor Opinion [Text Block]

Opinion on the Consolidated Financial Statements

We have audited the accompanying consolidated balance sheet of Avidia Bancorp, Inc. and Subsidiaries (the Company) as of December 31, 2025, and the related consolidated statements of operations, comprehensive income, changes in shareholders’ equity, and cash flows for the year then ended, and the related notes (collectively referred to as the consolidated financial statements). In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the consolidated financial position of the Company as of December 31, 2025, and the consolidated results of their operations and their cash flows for the year then ended, in conformity with U.S. generally accepted accounting principles.

 

We have also audited, in accordance with U.S. generally accepted auditing standards, the Company’s internal control over financial reporting as of December 31, 2025, based on criteria established in the Internal Control—Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) and our report dated March 27, 2026, expressed an unmodified opinion.

The consolidated financial statements of the Company as of December 31, 2024 were audited by other auditors whose report dated March 14, 2025, expressed an unqualified opinion on those statements.