Below are the planned opening and closing times of the main genealogy repositories over the Christmas 2022 and New Year 2023 period. They're all subject to change, so if you're travelling any distance, check the venue's website or, better, phone.
Republic of Ireland
DCL&A and all Dublin City Libraries will be closed from Christmas Eve to 2 January inclusive. Reopening 3 January.
Royal Irish Academy: Library closed from Saturday 24 December until Monday 9 January 2023 at 10am inclusive.
National Library of Ireland: Reading Room and Exhibitions closed from 5pm on Friday 23 December until 9:30am (10am for Seamus Heaney) on Tuesday 3 January.
National Archives of Ireland: Reading Room closed from 5pm Friday 23 December until 10am Tuesday 3 January.
General Register Office: Research Room closed from Friday 23 December to Monday 2 January inclusive. Email service will be available Friday 23 December, Wednesday 28, Thursday 29 and Friday 30 December. Normal service from Tuesday 3 January.
Local County and Branch Libraries: Most appear to be closed from Saturday 24 December to Tuesday 3 January but some are opening for just one day during that period. Check with each venue.
RCB Library:The Church of Ireland library and archive has unexcpectedly had to close its doors on Wednesday 21 and Thursday 22 December. It will be open, 9:30am to 1pm only on Friday 23 December and will not re-open until Tuesday 3 January.
Northern Ireland
Public Record Office of Northern Ireland (PRONI): Closed Monday 26 to Wednesday 28 December. Open Thursday 29 and Friday 30 December. Closed Monday 2 January. Returns to regular hours on Tuesday 3 January at 9am.
General Register Office of Northern Ireland (GRONI): Closed Monday 26 to Wednesday 28 December. Open Thursday 29 and Friday 30 December. Closed Monday 2 January. Returns to regular hours at 9:30am on Tuesday 3 January.
NILibraries / Local County and Branch Libraries: From Monday 19 to Friday 23 December inclusive, all libraries will close at 5pm. From Saturday 24 December to Monday 2 January 2023 inclusive, all libraries will be closed.
England & Wales
The National Archives, Kew, London: Closed Saturday 24 to Wednesday 28 December inclusive. Open Thursday 29 December and Friday 30 December. Closed Monday 2 January. Reopening Tuesday 3 January.
National Library of Wales: Closed from Saturday 24 December 2022 to Monday 2 January inclusive. Reopens 9am on Tuesday 3 January
Scotland
National Library of Scotland: Closed Saturday 24 to Tuesday 27 December inclusive. Open Wednesday 28 to Friday 30 December with revised hours. Closed Saturday 31 December to Tuesday 3 January inclusive. Reopening Wednesday 4 January.