NCUA-insured credit union

Mass Bay

Credit Union headquartered in South Boston, Massachusetts.
Source: NCUA call report data, data as of March 31, 2026, fetched September 5, 2026
Total assets
$367.71 million
Branches
4
NCUA-insured since
1994
Established
1936

Headquarters and contact

Address147 W 4Th St
South Boston, MA 02127
CountySuffolk
Websitenot published in NCUA data
Phone(617) 269-2700

NCUA record

NCUA Charter68137
Federal Reserve RSSD ID22196
StatusActive
Charter type2 (STATE)
Financials as ofMarch 31, 2026

Routing number

NCUA does not publish ABA routing numbers, and many credit unions use different routing numbers by state or by account type. The reliable places to find yours: the bottom left of a check from this credit union, the "account details" screen in its online banking, or its official website.
See how your odds compare before you apply at Mass Bay.

Offices

South Boston main office
South Boston, MA
147 W 4Th St, 02127
(617) 269-2700
8:45 AM to 4:15 PM
Everett
Everett, MA
183 Main St, 02149
(617) 269-2700
8:45am-4:15pm
Quincy Center
Quincy, MA
1250 Hancock St, 02169
(617) 269-2700
8:45 AM to 4:15 PM
Seaport Branch
South Boston, MA
409 D Street, 02127
(617) 269-2700
8:45 to 4:15 M-W, F8:45 to 6:00 Th

Where Mass Bay has offices

Other credit unions headquartered in South Boston

City of Boston$546.18 million
Taupa Lithuanian$29.58 million