Skip to content

OS MasterMap Topography Layer

OS MasterMap Topography Layer® is the most detailed and accurate view of Great Britain's landscape – from roads to fields, to buildings and trees, fences, paths and more.

In a business of any kind, OS MasterMap Topography Layer gives you the confidence to make location-based decisions about assets, services, environmental risks, customers and operations.

It helps you carry out effective scenario planning, improve resilience, manage public events and support security operations.

And for every type of business, OS MasterMap Topography Layer helps you to identify the landscape and explain the accurate ‘where’ of things.

Mapping from the ground up

Mapping from the ground up

OS MasterMap Topography Layer gives you access to the most detailed, current and comprehensive dataset of Great Britain. It offers an accurate visual context to help you interpret addresses, routes and imagery provided by other layers.

Start by using OS MasterMap Topography Layer as a definitive map for visualisation, then take advantage of advanced features later. With this data, you’ll make better-informed decisions about customers, operations, assets and environmental risks.

Building height data

Building height data

OS MasterMap Topography Layer now includes an enhanced feature - Building Height Attribute. Visualise buildings in 3D and use our data to analyse the built environment. 

Accurate referencing

Accurate referencing

OS MasterMap Topography Layer is ideal for geo-tagging your assets, thanks to the topographic identifier (TOID®) at the heart of OS MasterMap products. This makes it ideal for monitoring assets such as pipelines, pylons, bridges and warehouses.

Important sites mapped out

Important sites mapped out

OS MasterMap Sites Layer shows you the main points of access to key sites such as schools, hospitals and train stations quickly and easily in emergency situations. You can also identify and reduce the impact of planned works or events on key sites.


Technical specification
Key FeaturesWhat this product offers
ThemeOS MasterMap Topography Layer – buildings, heritage & antiquities. || OS MasterMap Sites Layer – education, medical care, rail transport, road transport, water transport, utility, and industrial.
Update frequencyOS MasterMap Topography Layer – every six weeks || OS MasterMap Sites Layer – every six months. || Building Height Attribute – every six months.
CoverageOS MasterMap Topography Layer – Great Britain (define your own area of interest or take advantage of pre-defined areas of interest). || OS MasterMap Sites Layer – Great Britain (order 5km2 tiles to cover your Topography Layer area of interest). || Building Height Attribute – Great Britain.
FormatOS MasterMap Topography Layer – GML 2.1.2 || OS MasterMap Sites Layer – GML 3.2.1 || Building Height Attribute – CSV


OS MasterMap Topography Layer is available under the following licence:

Explore our data

You’re welcome to try out this data for free under our Data Exploration Licence.

Internal business use

When using OS data in your own business, you need our Framework Contract (Direct Customers) together with a data contract.

Creating products or services 

To use this data commercially in your own products and services, or to distribute it, you will need to sign up to our Framework Contract (Partners) and a relevant defined use contract. This will vary depending on what you’re going to do with the data.

How to get this product

Sample data

Give it a try

Download a small area of OS MasterMap Topography Layer sample data

Or you can apply for a Data Exploration Licence to try out the real thing.

OS MasterMap Topography Layer FAQs

Case studies

Helping Northumbrian Water create the first underground utilities map

Delivering estimated savings of around £1 million, Northumbrian Water and Ordnance Survey (OS) created the first Underground Infrastructure Hub for the North East.

Helping to safeguard moorland life

Using OS data, the Moors for the Future Partnership created a land cover map which gave vital information to safeguard moorland life.

Using GIS to plan for housing growth

Ordnance Survey (OS) mapping enabled a local council to build an accurate picture of sites, which could be redeveloped for housing.