A "decree of the Eminent Senate of the Commonwealth of Ionian Islands" established the Ionian State Bank in 1839, to finance trade between the Ionian Islands (a British protectorate),
and Great Britain. This made the bank the oldest in Greece. The bank received a 20-year grant of the exclusive privilege of issuing and circulating banknotes for the Ionian Islands.
The bank soon changed its name to Ionian Bank (IB), and initially only operated in the Ionian Islands, opening branches in Corfu, Zakynthos and Kefalonia the following year. In 1845,
a year after the bank received a UK Royal Charter, it established agencies in Athens and Patras, and appointed special agents in Venice and Trieste.
In 1864, the Ionian Islands united with Greece and IB converted its agencies in Athens and Patras to full branches (possibly before 1864.)
IB then extended its operations to the rest of Greece. The Athens office took over as Head Office from the Corfu office in 1873. By 1880,
the bank lost its legal monopoly position in the Islands, but gained an extension to its (no longer exclusive) right of note issue. In 1883,
IB gave up its Royal Charter and registered as a limited liability company. Ionian Bank expanded into Egypt by opening branches in Alexandria in 1907.
