British Censuses
There are some isolated surviving earlier censuses for a few places in earlier years of the 1800s, (from 1801), but the first major national census of use to family historians was carried out in 1841. Subsequent censuses were taken every ten years, 1851, 1861 etc. (with the exception of 1941 during World War 2, when no census was taken).
Access to censuses is restricted under a 100 year rule. Therefore, the latest census that can be viewed by the public is the one for 1901 

A census was taken to record those living in a household at midnight on a Sunday.
The dates of the census varied from year to year.

Sun/Mon. 6/7th June 1841
Sun/Mon. 30/31st March 1851
Sun/Mon. 7/8th April 1861
Sun/Mon. 2/3rd April 1871
Sun/Mon. 3/4th April 1881
Sun/Mon. 5/6th April 1891
Sun/Mon. 31st March / 1st April 1901

Year

Municipal Borough

Town or village

 

1841

Westminster

London

View

1851

Westminster

London

View

Records 1 to 2 of 2

Link: http://www.british-genealogy.com/resources/census/index.htm