| 13072 | Armagh County Museum | 1960/153 | 1818-1851 | Case book, Dr William Lodge Kidd, 342 pages, 1818-18... | |
| 14989 | Armagh Diocesan Archive (RC) | | 1787-1818 | Full lists of these papers are available in the arch... | Most Reverend Richard Reilly Archive |
| 16169 | Birr Castle Archives | A-W | 1818 | E/13A: Small quarto recipe book of Alicia, wife of t... | The Rosse Papers |
| 16814 | Cashel, Ferns and Ossory Diocesan Archive (CoI) | | 1818-1823 | Lismore Estate?County Cork Estate Rent Book, 1818-18... | Bolton Library Archive |
| 16863 | Cashel, Ferns and Ossory Diocesan Archive (CoI) | | 1811-1818 | Lismore Estate:Lord Lismore's Letter Book, 1811-... | Bolton Library Archive |
| 16865 | Cashel, Ferns and Ossory Diocesan Archive (CoI) | | 1818 | Lismore Estate:Rental of lands of which Lord Lismore... | Bolton Library Archive |
| 16936 | Cavan County Archives | GJ/8 | 1818-1848 | [c. 1818-1848] Accounts book containing details of m... | Cavan Grand Jury Records |
| 4241 | Church of Ireland Centre | Ms131 | 1812-1818 | Letterbook containing copies of letters regarding th... | Records of the Society for Promoting the Education of the Poor of Ireland |
| 4293 | Church of Ireland Centre | Box 10 | 1818-1840 | Lithographed and Printed Papers, 1818-1840:Serial No... | Records of the Society for Promoting the Education of the Poor of Ireland |
| 554 | Cloyne Diocesan Archive (RC) | Box A | 1818-1836 | 1796.08/1/1818 Caroline Countess of Kingston to Wil... | Bishop W. Keane Papers |
| 17113 | Cloyne Diocesan Archive (RC) | Box J | 1818
1858 | 1796.06/62/1858 List of Sisters in Doneraile Conven... | Bishop W. Keane Papers |
| 19443 | Cloyne Diocesan Archive (RC) | Box B | 1818 | 1792.02/5/1818 Letter from Bishop Copinger, Cove, to... | Bishop Collins |
| 19457 | Cloyne Diocesan Archive (RC) | Box D | 1818 | 1791.00/2/1818 Hardback notebook, 'Visitation of... | Bishop Copinger |
| 1431 | Fingal County Archive | GJ/1/1- GJ/3/12 | 1818-1842 | GJ/1/1 1818-1841 Minutes and Orders, c.245 pages.GJ/... | County of Dublin Grand Jury |
| 5087 | Irish Architectural Archive | 97/84/Box 49 | 1773-1818 | Documents mostly financial in nature. Includes Thoma... | Castletown Papers |
| 14 | Irish Dominican Congregation Archives | A25 | 1818 | Typed extract from Whitelaw and Walsh's 'His... | Dominican Archives, Cabra |
| 4641 | Irish Jesuit Archives | FM/TULL/ | 1818 | 19 Typed copy of a letter from Maria O'Brien, Ra... | Papers of the Tullabeg Community Rahan, Tullamore, County Offaly |
| 21717 | Kerry Diocesan Archives (RC) | S94 | 1791-1818 | Accounts Book XX, includes details of expenditure, s... | Bishop Charles Sugrue, 1797-1825 |
| 5854 | King's Hospital School | 216-231 | 1818-1958 | 216 Letter Books, incoming, 1861 - 1861. 217 Prescr... | King's Hospital Records |
| 4999 | Maynooth University and St Patrick's College, Maynooth | Ms Murphy 44 | 1818-1820 | Translations into Irish from various religious tract... | |
| 20154 | Meath Local Studies and Family History Department | Box C/ | 1818 | 12 Letter acknowledging rent paid 1818 by J. Pollock... | Mountainstown Documents |
| 790 | National Archives of Ireland | 999/686 | 1818-1854 | 7 19 March 1818, Bargain and sale for remainder of 9... | |
| 4027 | National Archives of Ireland | | c1663-c1818 | Exchequer Revenue Exchequer, numbers RE95-RE176, c16... | Sarsfield Vesey Papers |
| 4865 | National Archives of Ireland | 999/836/3 | 1818 | Lease for 31 years by his Grace Eusby Lord Archbisho... | Mercer School Records |
| 8901 | National Archives of Ireland | M6934/14 | 1818 | Miscellaneous papers relating to the winding up of t... | Ballyglunin Papers |
| 15208 | National Archives of Ireland | 97/36 | 1803-1818 | St Paul's Parish, St Nicholas's Parish, Carrigaline ... | Selection of Private Accessions, 1980-2002 |
| 15498 | National Archives of Ireland | 999/113/3 | 1818 | Bargain and sale for remainder of 900 years by Willi... | Small Private Accessions |
| 15528 | National Archives of Ireland | 999/138/8 | 1818 | Settlement on the marriage of Joshua Smith, Streamst... | Small Private Accessions |
| 989 | National Library of Ireland | Ms11702 | 1818-1819 | An incomplete Rent Ledger of the King family, Ballyl... | |
| 1006 | National Library of Ireland | Mss12989 | 1818-1872 | Ledger of accounts of tenants on the Paul estates in... | |
| 1486 | National Library of Ireland | Ms1558 | 1818-1930 | An incomplete chronological list of orphans admitted... | |
| 1488 | National Library of Ireland | Ms1560 | 1818-1857 | Cashbook of Pleasants' Female Orphan Asylum, Dublin,... | |
| 1489 | National Library of Ireland | Ms1561 | 1818-1888 | Summary accounts of receipts and expenditure of Plea... | |
| 1561 | National Library of Ireland | Ms3275 | c1818 | Depositions on behalf of the Countess Dowager of Kin... | |
| 1940 | National Library of Ireland | Ms4639 | 1818 | An untitled poem signed Elize O'Neill, 18 August 181... | |
| 2029 | National Library of Ireland | Ms8334 | 1818-1827 | Miscellaneous papers which include copies of a marri... | Wade Papers |
| 2589 | National Library of Ireland | N558/ P928 | 1794-1818 | Maid Servants' Wage's Book, and other materi... | Pakenham-Mahon Papers |
| 2770 | National Library of Ireland | Ms21039 | 1818 | Inventory of kitchen furniture by Mrs Byrne [? at Ba... | Baker Papers |
| 3036 | National Library of Ireland | Ms9867 | 1818-1819 | A volume of poems by Lady Sophie Fitzgearld, 1818-18... | F.S. Bourke Collection |
| 3046 | National Library of Ireland | Ms9971 | 1818-1821 | Expenditure Accounts of Michael and Helena Bellew, B... | |
| 3484 | National Library of Ireland | Ms10831 | 1816-1818 | Seven letters to Isidore Blake from Mrs Peter Blake,... | Blake Papers |
| 3524 | National Library of Ireland | Ms11836 | 1818-1860 | Account Book of Miss Mary E L Trench in account with... | Domvile Papers |
| 3585 | National Library of Ireland | Mss12096-12097 | 1818-1873 | Minute Book of the Governors of (Thomas) Pleasants&#... | |
| 3586 | National Library of Ireland | Mss12099-12100 | 1818-1871 | Preacher's books relating to Female Orphan House... | |
| 3716 | National Library of Ireland | Ms12939 | 1818-1847 | Account Book of household expenses at Ballyglan, Cou... | |
| 3618 | National Library of Ireland | Ms12149 | c1700-1818 | Typescript catalogue of the correspondence of the Ho... | |
| 9025 | National Library of Ireland | Ms13748(9) | c1818-1834 | Letters from Lady Anne Fitzpatrick to John Price of ... | Fitzpatrick Papers |
| 9216 | National Library of Ireland | Ms15409 | 1818-1819 | Journal of a tour by Katherine Howard in France, Swi... | Wicklow Papers |
| 9626 | National Library of Ireland | Ms27358 | 1818-1841 | Miscellaneous letters, 1818-1841, including letters ... | O'Bryne Papers |
| 9629 | National Library of Ireland | Ms27364 | 1818 | Letters to Isaac Cahill from William Delany relating... | O'Bryne Papers |
| 10675 | National Library of Ireland | Ms16927 | 1806-1818 | Pages from the minute book of Commissioners of Educa... | Dr Michael Quane Papers |
| 16524 | Presentation Sisters Congregational Archives | DON1/1 | 1818-1903
1912-1968 | Annals of the convent in two volumes. (1) 1818-190... | Presentation Sisters South West Province - St Joseph's Convent, Doneraile |
| 16525 | Presentation Sisters Congregational Archives | DON1/4 | 1818-1967 | Noviceship register. Records civil name, name in re... | Presentation Sisters South West Province - St Joseph's Convent, Doneraile |
| 16526 | Presentation Sisters Congregational Archives | DON1/3 | 1818-1975 | Register of acts of reception and profession 1818-19... | Presentation Sisters South West Province - St Joseph's Convent, Doneraile |
| 16527 | Presentation Sisters Congregational Archives | DON1/67 | 1818-1976 | Register of admissions to convent national school. R... | Presentation Sisters South West Province - St Joseph's Convent, Doneraile |
| 16528 | Presentation Sisters Congregational Archives | DON1/37 | 1818-1974 | Monthly account books. Records expenditure only to D... | Presentation Sisters South West Province - St Joseph's Convent, Doneraile |
| 16529 | Presentation Sisters Congregational Archives | DON1/38 | 1818-1972 | Yearly account books. Income and expenditure double ... | Presentation Sisters South West Province - St Joseph's Convent, Doneraile |
| 7258 | Public Record Office of Northern Ireland | D/3432 | 1818-1852 | Minute Book of Knockbreda and Ballymacarret Dispensa... | |
| 7414 | Public Record Office of Northern Ireland | D/3975/1 | 1818 | Typed copy of a discursive letter regarding the gene... | |
| 6656 | Public Record Office of Northern Ireland | D/1835 | 1818-1897 | This collection of Greer, Hamilton and Gailey Solici... | Greer, Hamiliton, Gailey Solicitors Papers |
| 6712 | Public Record Office of Northern Ireland | D/1954 | 1818-1900 | This collection includes 86 rental books of Viscount... | |
| 6786 | Public Record Office of Northern Ireland | D/2249 | 1749-1818 | The Hamilton papers include: Reproduction portraits ... | Hamilton Papers |
| 7216 | Public Record Office of Northern Ireland | D/3127 | 1818-1920 | 8 letters to Mrs Martha Wallace, Belfast from variou... | |
| 7482 | Public Record Office of Northern Ireland | D/4149 | 1818-1864 | 6 diaries of James Harshaw of Donaghmore, County Dow... | |
| 7753 | Public Record Office of Northern Ireland | MIC/1C/ | 1818-1972 | Cullybackey Reformed Presbyterian Church, County Ant... | Reformed Presbyterian Church Records |
| 7870 | Public Record Office of Northern Ireland | T/1101 | 1776-1818 | A copy of a map with a list of tenants in Ballyholla... | |
| 7942 | Public Record Office of Northern Ireland | T/1282 | 1818-1883 | 4 volumes of negative photostat copies of the diarie... | |
| 8655 | Public Record Office of Northern Ireland | T/670/1 | 1814-1818 | Copy of a letter from Hugh Montgomery, Blessingbourn... | |
| 770 | Religious Society of Friends in Ireland Historical Library | QMII/P3 | 1818-1860 | Poor Committees and Charities: Female Bounty Fund, ... | Munster Quarterly Meeting |
| 3871 | Religious Society of Friends in Ireland Historical Library | Mss Box 45 | 1818-1842 | Grubb Collection: Letters, 1818-1842, concerning fam... | Handlists: Mss Boxes, Pamphlets Boxes, etc. |
| 4194 | Religious Society of Friends in Ireland Historical Library | Deed Box XII/Folder 4:10 | 1818 | Abigail Hautenvill, nee Jaffrey, daughter of Robert ... | Deeds |
| 5389 | Representative Church Body Library | D6/128-D6/130 | 1714-1818 | D6/128 Rent-Rolls of Archbishopric of Dublin, 1714.... | Diocese of Dublin |
| 23750 | Representative Church Body Library | Ms 517 | 1818-1919 | Minutes, 1818-1919; accounts, 1818-1888; admission r... | Kirwan House |
| 22437 | Royal Victoria Hospital, Belfast | | 1818-1947 | Belfast Royal Hospital Annual Reports:1818-18311832-... | |
| 13070 | Tipperary Museum of Hidden History | AQNO1995.161 | 1818 | Lease, Viscount Lismore to Mary John and James Norri... | |
| 13071 | Tipperary Museum of Hidden History | AQNO1995.162 | 1818 | Lease, Viscount Lismore to Mary John and James Norri... | |
| 10372 | Trinity College Dublin, Manuscripts and Archives Department | TCDMs2327 | 1818-1853 | Correspondence of Catherine (Kate) D'Alton and h... | |
| 3674 | UCC Special Collections & Archives | U267 | 1781-1818 | Letters of Sir Vere Hunt, includes: Lady Hunt's ... | |
| 18390 | University of Galway Archives | LA1 | 1485-1818 | The records of Galway Corporation from its foundatio... | Galway Corporation |
| 23325 | Waterford City Archives | P4/ | 1766-1818 | Two cash book recording the family's domestic in... | The Penrose Family Collection |