Heathrow Airport: Stanwell is beside Heathrow, not in central London. For most addresses, take a local bus from Terminal 5 or the Heathrow Central bus station—routes vary by stop and day—or use a licensed taxi for the short final leg. Expect roughly 15–30 minutes by road; a taxi is usually the sensible choice with luggage, at about £15–25 rather than paying for an airport transfer service.
Staines railway station: This is the useful rail gateway. South Western Railway trains link Staines with London Waterloo in roughly 35–50 minutes; from Staines, the bus to Stanwell takes about 20 minutes and costs around £2. A taxi is quicker, usually 10–15 minutes, but not dramatically so outside peak traffic.
London Waterloo: Take a South Western Railway train to Staines, then a local bus or taxi to Stanwell. Allow about 60–80 minutes door to door, including the connection. Do not take the Heathrow Express merely because Stanwell is near Heathrow: it delivers you to the airport, not the village, and adds an unnecessary transfer.