Banknotes have been issued for use specifically in Northern Ireland since 1929, and are denominated in pounds sterling. They are legal currency, but technically not legal tender anywhere (including Northern Ireland itself). However, the banknotes are still widely accepted as currency by larger merchants and institutions elsewhere in the United Kingdom. Issuing banks have been granted legal rights to issue currency, and back the notes with deposits at the Bank of England.
The issuing of banknotes in Northern Ireland is regulated by the Currency and Bank Notes Act 1928, the Coinage Act 1971, Banknotes (Ireland) Act 1864 (c. 78), Banknotes (Ireland) Act 1920 (c. 24), Bankers (Ireland) Act 1845, Bankers (Northern Ireland) Act 1928 (c. 15), among others.
Pursuant to some of these statutes, Her Majesty's Revenue and Customs publishes in the Belfast Gazette an account of "the Amount of Notes authorised by Law to be issued by the several Banks of Issue in Northern Ireland, and the Average Amount of Notes in Circulation, and of Bank of England Notes and Coin held"; see for example Issue 6800 published on 8 September 2006 at page 5874.
Notes were initially issued in denominations of 1, 5, 10, 20, 50 and 100 pounds. Of these denominations, only the 1 pound has ceased to be issued by all banks, with the last produced by the Allied Irish Banks in 1984. The 5 pound note is only issued now by Bank of Ireland and Ulster Bank, and Northern Bank stopped issuing notes over £20 when it was rebranded as Danske Bank.
Until April 2008, all Bank of Ireland notes featured Queen's University of Belfast on the reverse side. A new series of £5, £10 and £20 notes was issued in May 2008, all featuring an illustration of the Old Bushmills Distillery, and these notes will gradually replace the previous series.
The various denominations are differentiated by their colour and size:
First Trust Bank is a subsidiary of the Allied Irish Banks (AIB). AIB was originally formed in 1966 from a merger of a group of smaller banks. Following this merger, banknotes issued by the Provincial Bank of Ireland were reissued with the Allied Irish Banks name. In 1991, AIB merged with TSB Northern Ireland and began trading as the First Trust Bank, and since then, the bank's notes have been issued under the First Trust Bank name.