Chertsey is a town in the Borough of Runnymede, Surrey, England, 18 miles (29 km) south-west of central London. It grew up around Chertsey Abbey, founded in AD 666 by St Erkenwald, and gained a market charter from Henry I. A bridge across the River Thames first appeared in the early 15th century. The River Bourne through the town meets the Thames at Weybridge. The Anglican church has a medieval tower and chancel roof. The 18th-century listed buildings include the current stone Chertsey Bridge and Botleys Mansion. A curfew bell, rung at 8 pm on weekdays from Michaelmas to Lady Day ties with the romantic local legend of Blanche Heriot, marked by a statue of her and the bell at Chertsey Bridge. Green areas include the Thames Path National Trail, Chertsey Meads and a round knoll with remains of a prehistoric hill fort known as Eldebury Hill. Pyrcroft House dates from the 18th century and Tara from the late 20th. Train services are run between Chertsey railway station and London Waterloo by South Western Railway. The town is within the M25, accessible via junction 11. It has a population of 15,967.

The Borough of Runnymede is a local government district with borough status in Surrey, England. Its council is based in Addlestone and the borough also includes the towns of Chertsey and Egham. The borough is named after Runnymede, a water meadow on the banks of the River Thames near Egham, which is connected with the sealing of Magna Carta by King John in 1215.