# List of United Kingdom parliamentary constituencies in Ireland 1801–1885

Under the Acts of Union 1800, with effect from 1 January 1801, there were a 100 MPs representing Ireland in the United Kingdom Parliament. These were divided into 66 constituencies for elections to the United Kingdom Parliament, specified as "two for each County of Ireland, two for the City of Dublin, two for the City of Cork, one for the University of Trinity College, and one for each of the thirty-one most considerable Cities, Towns, and Boroughs":
* 32 county constituencies, each electing 2 MPs;
* 33 borough constituencies, each electing 1 MP, except for Cork City and Dublin City, which elected 2 MPs; and
* 1 university constituency, electing 1 MP.
This distribution remained substantively until 1885, subject to the following alterations:
* Representation of the People (Ireland) Act 1832: the total number of seats from Ireland increased to 105, with Belfast, Galway Borough, Limerick City, Waterford City and Dublin University gaining a second seat.
* Parliamentary Boundaries (Ireland) Act 1832: minor boundary changes to the borough constituencies.
* Representation of the People (Ireland) Act 1868: in the case of boroughs retained under the Municipal Corporations (Ireland) Act 1840, boundaries of parliamentary boroughs extended to include the whole municipal borough.
* Sligo and Cashel Disfranchisement Act 1870: the boroughs of Cashel and Sligo were disfranchised for corruption, reducing the number of constituencies to 64 and seats to 103.
In the Redistribution of Seats Act 1885, there was a substantial revision of constituencies, taking a greater account of changes to the population. Most borough constituencies were abolished and county constituencies were divided into single-member districts. These new constituencies were first used at the 1885 United Kingdom general election in Ireland.

## List of constituencies

^ *: Disfranchised in 1870.
| Constituency | Type | County | Seats | Seats |
| Constituency | Type | County | 1801 | 1832 |
| County Antrim | County | County Antrim | 2 | 2 |
| County Armagh | County | County Armagh | 2 | 2 |
| Armagh | Borough | County Armagh | 1 | 1 |
| Athlone | Borough | County Westmeath | 1 | 1 |
| Bandon | Borough | County Cork | 1 | 1 |
| Belfast | Borough | County Antrim | 1 | 2 |
| County Carlow | County | County Carlow | 2 | 2 |
| Carlow | Borough | County Carlow | 1 | 1 |
| Carrickfergus | Borough | County Antrim | 1 | 1 |
| Cashel | Borough | County Tipperary | 1 | 1 |
| County Cavan | County | County Cavan | 2 | 2 |
| County Clare | County | County Clare | 2 | 2 |
| Clonmel | Borough | County Tipperary | 1 | 1 |
| Coleraine | Borough | County Londonderry | 1 | 1 |
| County Cork | County | County Cork | 2 | 2 |
| Cork | Borough | County Cork | 2 | 2 |
| County Donegal | County | County Donegal | 2 | 2 |
| County Down | County | County Down | 2 | 2 |
| Downpatrick | Borough | County Down | 1 | 1 |
| Drogheda | Borough | County Louth | 1 | 1 |
| County Dublin | County | County Dublin | 2 | 2 |
| Dublin | Borough | County Dublin | 2 | 2 |
| Dublin University | University | County Dublin | 1 | 2 |
| Dundalk | Borough | County Louth | 1 | 1 |
| Dungannon | Borough | County Tyrone | 1 | 1 |
| Dungarvan | Borough | County Waterford | 1 | 1 |
| Ennis | Borough | County Clare | 1 | 1 |
| Enniskillen | Borough | County Fermanagh | 1 | 1 |
| County Fermanagh | County | County Fermanagh | 2 | 2 |
| County Galway | County | County Galway | 2 | 2 |
| Galway | Borough | County Galway | 1 | 2 |
| County Kerry | County | County Kerry | 2 | 2 |
| County Kildare | County | County Kildare | 2 | 2 |
| County Kilkenny | County | County Kilkenny | 2 | 2 |
| Kilkenny | Borough | County Kilkenny | 1 | 1 |
| King's County | County | King's County | 2 | 2 |
| Kinsale | Borough | County Cork | 1 | 1 |
| County Leitrim | County | County Leitrim | 2 | 2 |
| County Limerick | County | County Limerick | 2 | 2 |
| Limerick | Borough | County Limerick | 1 | 2 |
| Lisburn | Borough | County Antrim | 1 | 1 |
| County Londonderry | County | County Londonderry | 2 | 2 |
| Londonderry | Borough | County Londonderry | 1 | 1 |
| County Longford | County | County Longford | 2 | 2 |
| County Louth | County | County Louth | 2 | 2 |
| Mallow | Borough | County Cork | 1 | 1 |
| County Mayo | County | County Mayo | 2 | 2 |
| County Meath | County | County Meath | 2 | 2 |
| County Monaghan | County | County Monaghan | 2 | 2 |
| New Ross | Borough | County Wexford | 1 | 1 |
| Newry | Borough | County Down | 1 | 1 |
| Portarlington | Borough | Queen's County | 1 | 1 |
| Queen's County | County | Queen's County | 2 | 2 |
| County Roscommon | County | County Roscommon | 2 | 2 |
| County Sligo | County | County Sligo | 2 | 2 |
| Sligo | Borough | County Sligo | 1 | 1 |
| County Tipperary | County | County Tipperary | 2 | 2 |
| Tralee | Borough | County Kerry | 1 | 1 |
| County Tyrone | County | County Tyrone | 2 | 2 |
| County Waterford | County | County Waterford | 2 | 2 |
| Waterford | Borough | County Waterford | 1 | 2 |
| County Westmeath | County | County Westmeath | 2 | 2 |
| County Wexford | County | County Wexford | 2 | 2 |
| Wexford | Borough | County Wexford | 1 | 1 |
| County Wicklow | County | County Wicklow | 2 | 2 |
| Youghal | Borough | County Cork | 1 | 1 |