There are 11 different classes of PRSI, which fall broadly under the following 5 headings:
employees in the private sector and certain public servants (Classes A, E and J)
certain public servants (Classes B, C, D and H)
self-employed people, this includes company shareholders controlling over 50% of shares. (Class S) . Class S and P applies to certain self-employed share-fishermen.
people who pay no PRSI (Class M)
certain Public Office Holders (Class K).
The following is a brief description of the people covered by each of the main PRSI contribution classes.
Employees in industrial, commercial and service-type employment with gross earnings of €38 or more a week from all work; civil and public servants recruited from 6 April 1995 and Community Employment workers from 6 April 1996. (Most workers in Ireland pay Class A PRSI contributions).
certain public office holders (the President, the holder of a 'qualifying office', members of the Oireachtas, the judiciary, certain military judges, the Attorney General, the Comptroller and Auditor General, members of a local authority and certain members of the European Parliament), who earn over €5,200 a year. These Public Office holders pay PRSI at a rate of 4% on all income.
any of these specified public office holders who earn €5,200 a year or less (€100 a week or less) have a nil liability – see Class M.
From 1st January 2013, Class K also applies to the additional earned self-employed income from a trade or profession of a modified rate contributor and on any unearned income they have
From 1 January 2014, employed contributors and occupational pensioners aged under 66 years whose only additional income is unearned may be liable for PRSI contributions on this income.
Self-employed people such as farmers, certain company directors, sole traders and certain people with income from investments, rents and maintenance, where the income is €5,000 or more a year from all sources.