Its greatest length north to south is only and its greatest breadth east to west is . It has the smallest population of any normal unitary authority in mainland England and only the City of London is smaller in terms of area. It is 348th of the 354 districts in population. It is the smallest historic county in England and the fourth smallest in the UK as a whole. Because of this, the Latin motto Multum in Parvo or "much in little" was adopted by the county council in 1950. Among modern ceremonial counties the Isle of Wight, City of London and City of Bristol are smaller. The former County of London, in existence 1889 to 1965, also had a smaller area.
The only towns in Rutland are Oakham, the county town, and Uppingham. At the centre of the county is the large artificial reservoir, Rutland Water, which is an important nature reserve serving as an overwintering site for wildfowl and a breeding site for ospreys.
Earl of Rutland and Duke of Rutland are titles in the peerage of England, derived from the historic county of Rutland. The Earl of Rutland was elevated to the status of Duke in 1703 and the titles were merged. The family seat is Belvoir Castle.
Rutland covered parts of three poor law unions and rural sanitary districts: those of Oakham, Uppingham and Stamford. The registration county of Rutland contained the entirety of Oakham and Uppingham RSDs, which included several parishes in Leicestershire and Northamptonshire – the eastern part in Stamford RSD was included in the Lincolnshire registration county.
In 1894 under the Local Government Act 1894 the rural sanitary districts were partitioned along county boundaries to form three rural districts. The part of Oakham and Uppingham RSDs in Rutland formed the Oakham Rural District and Uppingham Rural District, with the two parishes from Oakham RSD in Leicestershire becoming part of the Melton Mowbray Rural District, the nine parishes of Uppingham RSD in Leicestershire becoming the Hallaton Rural District, and the six parishes of Uppingham RSD in Northamptonshire becoming Gretton Rural District. Meanwhile, that part of Stamford RSD in Rutland became the Ketton Rural District.
Oakham was split out from Oakham Rural District in 1911 as an urban district.
Rutland was included in the "East Midlands General Review Area" of the 1958–67 Local Government Commission for England. Draft recommendations would have seen Rutland split, with Ketton Rural District going along with Stamford to a new administrative county of Cambridgeshire, and the western part added to Leicestershire. The final proposals were less radical and instead proposed that Rutland become a single rural district within the administrative county of Leicestershire.
This action was to prove only temporary, with Rutland being included in the new non-metropolitan county of Leicestershire under the Local Government Act 1972, from 1 April 1974. Under proposals for non-metropolitan districts Rutland would have been paired with what now constitutes the Melton district – the revised and implemented proposals made Rutland a standalone non-metropolitan district (breaking the 40,000 minimum population barrier).
In 1994, the Local Government Commission for England, which was conducting a structural review of English local government, recommended that Rutland become a unitary authority. This was implemented on 1 April 1997, with Rutland regaining a separate Lieutenancy and shrievalty as well as its council regaining control of county functions such as education and social services.
Royal Mail included Rutland in the Leicestershire postal county in 1974. After a lengthy and well-organised campaign, and despite a code of practice which excludes amendments to former postal counties, the Royal Mail agreed to create a postal county of Rutland in 2007. This was achieved in January 2008 by amending the former postal county for all of the Oakham (LE15) post town and a small part of the Market Harborough (LE16) post town.
The council remained formally a non-metropolitan district council, with wards rather than electoral divisions, but has renamed the district to 'Rutland County Council' to allow it to use that name. This means the full legal name of the council is Rutland County Council District Council.
Under the Poor Laws, Oakham Union workhouse was built in 1836–37 at a site to the north-east of the town, with room for 100 paupers. The building later operated as the Catmose Vale Hospital, and now forms part of the Oakham School.