| Preston Crowmarsh | |
|---|---|
 Cottages in Preston Crowmarsh | |
  Preston Crowmarsh Location within Oxfordshire | |
| OS grid reference | SU616908 |
| Civil parish | |
| District | |
| Shire county | |
| Region | |
| Country | England |
| Sovereign state | United Kingdom |
| Post town | Wallingford |
| Postcode district | OX10 |
| Dialling code | 01491 |
| Police | Thames Valley |
| Fire | Oxfordshire |
| Ambulance | South Central |
| UK Parliament | |
| Website | Benson Parish Council |
Preston Crowmarsh is a hamlet in Benson civil parish in South Oxfordshire. It is on the River Thames 1 mile (1.6 km) north of Wallingford. The river can be crossed on foot here at Benson Lock.