This web page provides information about online resources for census research - transcriptions, indexes, searchable databases, &c. Select a year below, or start with 'All Years' and browse the whole page.
Original census returns are held by The National Archives and are not available generally for direct research, but copies on film or fiche are available at LDS Family History Centers worldwide. Returns are available for all parishes in Monmouthshire at Monmouthshire Libraries in Abergavenny, Caldicot, Chepstow and Monmouth, but please check availability with the Offices themselves before your journey.
FreeCEN is an ongoing volunteer-based project to provide a 'free to view' online searchable database of the 19th century UK census returns. Volunteers are being sought to assist with transcribing - visit the FreeCen Project page to see each county's status as well as a FAQ for volunteers.
Index of names, and downloadable images of Census 1841-1901 are available from Ancestry.co.uk. Access is by Annual subscription, or Pay-per-View. A subscription includes access to other Ancestry resources.
Search the 1901 Census online for free. Pay-per-image (currently £0.75) by Vouchers or Credit Card to view an image of the original return. A pioneering effort by QinetiQ, now (Sep 2005) being developed by Genes Reunited.
Free search by name of the 1881 Census at Ancestry.com. Access to images is by Annual subscription, or Pay-per-View. A subscription includes access to other Ancestry resources. The index for this service is provided by The Church of Jesus Christ of Latter-day Saints (LDS); images are reproduced by courtesy of The National Archives.
The same 1881 data is also available for searching free of charge at IGI and Familysearch, but without access to the digital images. It is also available for purchase on CD from various outlets.
Free search by name of the 1861 Census at Ancestry.com. Access to images is by Annual subscription, or Pay-per-View. A subscription includes access to other Ancestry resources.
The 1861 census is also available for searching at findmypast.com (formerly 1837online). Although generally speaking, this site works well for the Civil Registration Indexes that it was designed for, I haven't explored the 1861 census access.