The Central Bank announced its intention for the new banknotes in December 1971 and Servicon, an Irish design company, was employed to design the notes of the denominations; £1, £5, £10, £20, £50 and £100. The £100 note was never issued or circulated; this remains somewhat of an idiosyncrasy in the issue of Irish banknotes as this is the only series without a note of this denomination. The series was Legal Tender from 1976-1995, although not printed after May 1993. The theme chosen for these notes was history of Ireland, and each note featured the portrait of a person with this theme in mind from a particular era from historic to modern and complementing visual elements. The female head painted by Sir John Lavery was retained from Series A; contained in the unprinted space. Each banknote has the signature of the Governor of the Central Bank of Ireland and the Secretary of the Department of Finance. During much of the period of circulation of this series, foreign exchange controls prohibited the export of any notes larger than £20 from the Republic.
One Pound
The greenone pound note had a portrait of Medb, the legendary Queen of Connacht in Irish mythology. Also a pre-Christian geometric design based on those found on bone slips is used in on the note, the background is an excerpt from the Táin. The reverse had a decorated excerpt from Lebor na hUidre, the oldest surviving Irish manuscript, with some red in addition to the dominant green. The dimension of the notes are 78.0 × 148.0 millimetres. The one pound note was removed from circulation from June 1990 as it was replaced by the Irish pound coin, this note was the final one pound note to be circulated and it was the first note of Series B to be removed from circulation.
The purple ten pound had a portrait of Dean Jonathan Swift the poet and satirist. The background contains a reproduction of the coat of arms of Dublin from a city council resolution against a letter by Swift from April 1735. The reverse had a portion of a map of Dublin which was published by John Rocque in 1756. Great Abbey Street and Astons Quay - now known as Middle Abbey Street and Aston Quay respectively are shown as well as the River Liffey. The dimension of the notes are 86.0 X 164.0 millimetres. The note consists of shades of purple - three shades on the front and two on the back.
The red-brown fifty pound note had a portrait of Turlough O'Carolan, the blind Irish harper and composer, with the background from Timbrell. The reverse had a design based on the wood carvings on the organ loft of St. Michan's Church, Dublin. The dimension of the notes are 94.0 X 180.0 millimetres. Using the red-brown colours it is set using five shades on the front and four on the back.
One Hundred Pounds
A Series B hundred pound note was never issued, the Series A £100 note remained in circulation. A design pattern was done for a £100 denomination, but it was not required by the Central Bank of Ireland. Although during the late 1970s some newspapers reported that a planned £100 note would have been Mauve in colour and would have had Grace O'Malley on the front, the Galtee Mountains on the reverse and the dimension of the notes in size 188 x 98 mm.