Chalfont St Peter is a village and civil parish in south-east Buckinghamshire, England. It is in a group of villages called The Chalfonts which also includes Chalfont St Giles and Little Chalfont. The villages lie between High Wycombe and Rickmansworth. Chalfont St Peter is one of the largest villages, with nearly 13,000 residents. The urban population for Chalfont St Peter and Gerrards Cross is 19,622, the two villages being considered a single area by the Office for National Statistics.

Gerrards Cross was once a hamlet in the parish of Chalfont St Peter, but became a village and civil parish in its own right and is now a town.

Chalfont St Peter is 19.8 miles (31.9 km) west-north-west of Charing Cross, central London and is also in close proximity to Heathrow Airport, Pinewood and Elstree film studios, and the motorway network (M25, M40, M1 and M4).

Chalfont St Peter is one of the largest villages in the United Kingdom partly due to the proximity to Gerrards Cross railway station which lies between London Marylebone and Birmingham Snow Hill on the Chiltern Main Line. Modern buildings and urbanisation now dominate the village centre and very little historic architecture remains. The first major development of the village were rows of Georgian shops (some of which still remain). Much larger developments came in the late 1920s and these shops that run up the main street towards Gold Hill common now comprise most of the village centre. Modernisation and urbanisation continued up until the 1960s when most of the Georgian shops were demolished in favour of a concrete development of flats, offices and shops fronts surrounding a central car park.

Chalfont St Peter is often described as the Gateway to the Chiltern Hills. It is not a major tourist centre but has many places to stay, the most notable being The Greyhound (former local court house where hangings took place), which is situated at the foot of the village on the banks of the River Misbourne. Nearby there are several manor houses of note, as well as many museums, cottages and parks. Milton's Cottage in Chalfont St Giles, the Colne Valley regional park, Bekonscot Model Village, Chenies Manor House, the Chiltern Open Air Museum, Odds Farm Park, Cliveden, Dorney Court, Harrow Museum & Heritage Centre, Royal Windsor Racecourse and Hughenden Manor are the nearest attractions to the village itself. The Chiltern Open Air Museum is situated mainly within the village.