In 1892, the African Banking Corporation and the Bank of British West Africa, now First Bank of Nigeria Limited was established and have a membership of ASSBIFI at above 6300. Union Bank of Nigeria was founded in 1917 with over 917 ASSBIFI members. Wema Bank Nigeria was established in 1945 with over 1317 as ASSBIFI members. United Bank for Africa was founded in 1949 and has over 9,287 ASSBIFI members. Federal Mortgage Bank of Nigeria was established in 1956 with over 257 ASSBIFI members. Bank of Industry Nigeria started operation in 1959 as Investment Corporation of Nigeria (ICON) and later reconstructed out of the Nigerian Industrial Development Bank (NIDB), Nigerian bank for Commerce and Industry (NBCI), and later the National Economic Reconstruction Fund (NERFUND). ASSBIFI identifies with the Bank.

Others are Bank of Agriculture Nigeria, Established in 1972 and has about 18,372 ASSBIFI members.  Sterling Bank, Incorporated in 1980 and has about 2,243 ASSBIFI members. First City Monument Bank Nigeria was established in 1982 with about 2000 ASSBIFI members. Citibank Nigeria was founded in 1984 and membership of ASSBIFI is 2. Eco Bank Nigeria started operation in 1986 and has 2695 unionized staff.  Polaris Bank Nigeria has its origin dating back to 1989 and currently has over 5000 ASSBIFI members. Heritage Bank Nigeria was founded in 1989 and membership of ASSBIFI is about 10,000.  Access Bank of Nigeria was established in 1989 and membership of ASSBIFI is over 9000.  Zenith Bank Nigeria was founded in 1990 and presently has over 700 ASSBIFI members. Unity Bank of Nigeria was established in 2006 and membership of ASSBIFI is about 5000. Keystone Bank Nigeria was established in 2011 and membership of ASSBIFI is about 5000.

Efforts are currently on to get other Banks employees currently operating in Nigeria to unionize and take global advantage of belonging to a democratic organization.