OS MasterMap® contains sophisticated and highly accurate high quality map data in layers, to help you visualise the information you need to support decision making and analysis.
To learn more about OS MasterMap, you may want to start with understanding how we define the data and the terms and data measures we use.
Publication and refresh dates
OS MasterMap data is regularly updated or published to help you maintain a timely and accurate picture of Great Britain. Details on then these updates take place can be found below.
- For a detailled list of refresh and publication dates, visit the refresh dates page.
- Find out more about OS MasterMap Schema history.
Managed GB Datasets
This service allows you to process identical orders faster, which improves delivery times. If you subscribe to this service you will automatically receive your updates (full supply or change-only updates (COU)) on CD or DVD, either quarterly or every six weeks. Find out more about managed GB datasets.
Content improvement programme:
Find out more about urban content improvement.
Planned improvement to fulfilment:
Find out more about planned improvements to customer fulfilment.
- What is the Integrated Transport Network Layer?
The OS MasterMap® Integrated Transport Network (ITN) Layer is the definitive national road network for Great Britain. It provides a flexible foundation for publishing, transport, telematic and asset-management solutions and can be fully integrated with all OS MasterMap layers; for example, within OS MasterMap Address Layer for to-the-door routing.
- What are the main components of Sites?
Sites consist of three features: the functional site extent, access points and routing points. These features reference each other and other layers of OS MasterMap, as well as other Ordnance Survey products such as AddressBase. Detailed attribution is also provided for all the features within the product.