Newton Leys is a district that covers the southern tip of Bletchley (a constituent town of Milton Keynes) and straddles the boundary between the City of Milton Keynes and the rest of Buckinghamshire. The larger fraction of Newton Leys lies within Milton Keynes and forms a part of Bletchley and Fenny Stratford civil parish. It is separated from central Bletchley, Water Eaton and the Lakes Estate by the West Coast Main Line. The remaining fraction of Newton Leys lies within the (former) Aylesbury Vale district and forms a part of the Stoke Hammond civil parish, although the village of Stoke Hammond is situated on the other side of the A4146Newton Leys within Milton Keynes is a brownfield development and within the Buckinghamshire Council area is greenfield. The full district covers some 104 hectares (260 acres) and comprises development land with housing for up to 1650 homes with employment areas, shops, a school, community facilities, new park, hotel, a care home and leisure facilities built on two former brickworks and farmland. The site is being developed by Taylor Wimpey. Houses have been built at the development by Taylor Wimpey South Midlands, Taylor Wimpey North Thames, Persimmon, and Bovis Homes Group.
The development area sits next to a man-made lake created from the brick making industry, a claypit was flooded to form Jubilee Lake, which has since become known as Willow Lake. The lakes at Newton Leys form part of a sustainable drainage system/balancing lake system designed to manage excess water caused by heavy or prolonged rainfall. Jubilee Brooks runs through the centre of the development, which rises north of Drayton Parslow and flows through the settlement towards the West Coast Mainline passing through to the Lakes Estate where it joins with the Water Eaton Brook, eventually flowing into the River Ouzel.Newton Leys is bordered by the A4146, the Bletchley Landfill Site operated by FCC Environment, Blue Lagoon Local Nature Reserve, Newton Longville and Stoke Hammond. The Oxford–Bletchley railway line runs along the northern border of the site, whilst the West Coast Main Line runs to the east of the site.