The settlement was reached over breaches of the Criminal Justice (Money Laundering and Terrorist Financing) Act
The Central Bank has imposed a fine of €98,000 on Bray Credit Union in County Wicklow.
A settlement has been reached on breaches of the Criminal Justice Act 2010.
Bray Credit Union has almost 27,000 members, and is in the top 11% of Ireland's credit unions by asset size.
According to the Central Bank, there were 'significant failings' in the credit union's 'anti-money laundering / countering of the financing of terrorism' (AML / CFT) framework and procedures.
The Central Bank says the majority of breaches persisted for more than five years, with all but one taking place between July 2010 to February 2016. Bray Credit Union is said to have admitted to the breaches.
Central Bank Director of Enforcement, Derville Rowland, said: "The Central Bank is concerned that a credit union of its size and scale was found to have breached key AML/CFT requirements for such an extended period of time. The breaches identify significant failings by Bray Credit Union in crucial areas such as the adoption of adequate policies and procedures, customer due diligence and monitoring dealings with members.
"The failure by Bray Credit Union to apply adequate identification and verification measures to members and to scrutinise their transactions meant that it lacked critical information to allow it to properly fulfil its obligations to monitor, identify and report unusual and potentially suspicious activity and created an unacceptable risk of money laundering and terrorist financing," she added.