The coldest nights of the year in the UK going back to 1875. The majority of the list was taken from the once-existing UK annual minimum temperature list from TORRO although updated and changed over the last few years by me. I will be happy to correct and update any years based on any new data if it turns up!
19th Century
1875
-14.7°C Hawes 01/01
1876
-12.2°C Buxton 11/02
1877
-15.6°C Braemar 03/01
1878
-18.9°C Gainford 13/12
1879
-26.7°C Kelso 03/12
1880
-17.7°C Braemar 27/12
1881
-26.7°C Kelso 17/01
1882
-22.4°C Braemar 15/12
1883
-15.1°C Alston 15/03
1884
-12.5°C Kingussie 03/01
1885
-14.9°C Braemar 16/01
1886
-18.9°C Alston 07/03
1887
-15.3°C Marlborough 17/03
1888
-17.2°C Lairg 16/02
1889
-14.8°C Logie Coldstone 05/03
1890
-17.4°C Stokesay 22/12
1891
-17.2°C Ketton 18/01 & Lairg 12/03
1892
-22.2°C Scaleby 19/02
1893
-20.0°C Braemar 06/01
1894
-20.2°C Hodsock 06/01
1895
-27.2°C Braemar 11/02
1896
-12.8°C Braemar 23/12
1897
-21.7°C Braemar 04/02
1898
-16.1°C Braemar 24/02
1899
-16.1°C Braemar 21/03
20th Century
1900
-19.4°C Braemar 11/02
1901
-18.8°C Swarraton 09/01
1902
-18.9°C Lairg 14/02
1903
-17.2°C Braemar 13/01
1904
-14.4°C Appleby 27/11
1905
-15.0°C Braemar 18/11
1906
-16.8°C Woodbridge 30/12
1907
-15.0°C Llangammarch Wells 25/01
1908
-18.3°C Liphook 30/12
1909
-17.8°C Marlborough 03/03 & Balmoral 07/12
1910
-23.3°C Balmoral & Logie Coldstone 28/01
1911
-12.2°C Galforth 01/02
1912
-20.6°C West Linton 04/02
1913
-15.6°C Braemar 31/12
1914
-13.9°C Braemar 25/12
1915
-13.3°C Balmoral 05/12
1916
-16.7°C Braemar 20/02
1917
-20.0°C Benson 06/02
1918
-19.4°C West Linton
1919
-23.3°C Braemar 14/11
1920
-18.3°C Raunds 13/12
1921
-15.0°C Braemar 14/11
1922
-13.3°C West Linton, Eskdalemuir & Garforth 18/01
1923
-14.4°C Braemar 25/12
1924
-16.7°C Balmoral 03/03
1925
-16.7°C Braemar 20/12
1926
-16.7°C Luton 17/01
1927
-17.8°C Braemar 18/12 & Logie Coldstone 17 & 18/12
1928
-13.3°C Braemar 01/01
1929
-18.3°C Usk & Ross-on-Wye 14/02 & Houghall 17/02
1930
-16.1°C Newport 20/03
1931
-17.2°C Braemar 03/03
1932
-11.7°C Dalwhinnie 12/03
1933
-15.6°C Logie Coldstone 19/01
1934
-12.2°C Braemar 14/03
1935
-15.6°C Braemar 24/12
1936
-15.0°C Braemar 05 & 13/02
1937
-21.7°C Braemar 13/12
1938
-15.6°C Braemar 22/12
1939
-17.2°C Dalwhinnie & Braemar 04/01
1940
-23.3°C Rhayader 21/01
1941
-21.1°C Houghall 05/01 & West Linton 06/01
1942
-19.4°C Braemar 08/03
1943
-13.9°C Braemar 05/01
1944
-15.0°C Braemar 28/02
1945
-19.4°C Dalwhinnie 26/01
1946
-14.4°C Dalwhinnie 26/02
1947
-21.3°C Elmstone (Kent) 30/01
1948
-15.6°C Logie Coldstone 24/01
1949
-17.8°C Braemar 05/01
1950
-18.3°C Dalwhinnie 15/12
1951
-16.1°C Dalwhinnie 11/03
1952
-17.2°C Logie Coldstone 30/01
1953
-12.8°C Braemar & Dalwhinnie 03/01
1954
-20.0°C Welshpool 02/02
1955
-25.0°C Braemar 23/02
1956
-18.9°C Perth 03/01
1957
-16.1°C Sutton Bonnington 20/02
1958
-22.8°C Logie Coldstone 14/03
1959
-17.8°C Braemar 15/01 & Kincraig 04/02
1960
-22.2°C Grantown-on-Spey 18/02
1961
-22.2°C Cannich 30/12
1962
-21.1°C Corwen 02/01
1963
-22.2°C Braemar 18/01
1964
-15.6°C Caldecott 29/12
1965
-21.7°C Corwen 03/03
1966
-20.0°C Braemar 15/02
1967
-14.4°C Carnwath 10/12
1968
-18.3°C Braemar 21/02
1969
-20.6°C Grantown-on-Spey 18/02
1970
-21.1°C Carnwath & West Linton 21/01
1971
-12.8°C Braemar 04/01
1972
-18.5°C Moorhouse 31/01
1973
-21.2°C Carnwath 15/02
1974
-10.2°C Lagganlia 14/02
1975
-11.4°C Balmoral 08/02
1976
-16.2°C Carnwath 05/12
1977
-18.7°C Lagganlia 17/01
1978
-22.0°C Keith 20/02
1979
-24.6°C Carnwath 13/01
1980
-17.5°C Clashnoir 02/01
1981
-25.2°C Shawbury 13/12
1982
-27.2°C Braemar 10/01
1983
-14.2°C Lagganlia 19/02
1984
-23.6°C Grantown-on-Spey 20/01
1985
-23.4°C Lagganlia 27/01
1986
-21.2°C Grantown-on-Spey 27/02
1987
-19.1°C Warsop 13/01
1988
-11.6°C Carnwath 22/11
1989
-14.0°C Tummel Bridge 15/12
1990
-8.4°C Grantown-on-Spey 15/02
1991
-16.0°C Cawood 14/02
1992
-14.2°C Grantown-on-Spey 21/12
1993
-15.8°C Altnaharra 26/12
1994
-16.1°C Braemar 17/02
1995
-27.2°C Altnaharra 30/12
1996
-13.0°C Aviemore 25/12
1997
-14.5°C Santon Downham 03/01
1998
-17.0°C Altnaharra 01/03
1999
-14.0°C Sennybridge 20/12
21st Century
2000
-15.0°C Dalmally 30/12
2001
-21.7°C Kinbrace 03/03
2002
-16.1°C Grantown 02/01
2003
-18.3°C Aviemore 07/01
2004
-15.2°C Kinbrace 19/12
2005
-13.2°C Ravensworth 29/12
2006
-16.4°C Altnaharra 02/03
2007
-13.0°C Aboyne 22/12
2008
-12.9°C Aviemore 30/12
2009
-18.4°C Aviemore 09/02 & Braemar 29/12
2010
-22.3°C Altnaharra 08/01
2011
-13.0°C Altnaharra 08/01
2012
-18.3°C Chesham 11/02
2013
-13.4°C Marham 16/01
2014
-9.0°C Cromdale 27/12
2015
-12.5°C Tulloch Bridge 19/01
2016
-14.1°C Braemar 14/02
2017
-13.0°C Shawbury 12/12
2018
-14.2°C Brogdale 28/02
2019
-15.4°C Braemar 01/02
2020
-10.2°C Braemar 13/02 & Dalwhinnie 30/12
2021
-23.0°C Braemar 11/02
2022
-17.3°C Braemar 13/12
2023
-16°C Altnaharra 09/03