Purchasing OS Maps for Your Planning Application

Twenty-two percent of planning applications that get bounced as invalid fail for one reason: the location plan doesn't meet the council's criteria. Not the drawings. Not the design. The map. It's the single most common reason for invalidation across England, and it delays your application by weeks while you sort it out and resubmit.

The good news is that getting your maps right is one of the cheapest and simplest parts of the entire planning process. The maps you need for your application cost £10 – £40 in total, and the whole ordering process takes about ten minutes online.

What Maps You Need and Why

Every householder planning application requires two separate Ordnance Survey map extracts. Not Google Maps screenshots. Not Apple Maps printouts. Not hand-drawn sketches. Licensed OS data, purchased from an approved provider, with the Ordnance Survey copyright notice and licence number printed on them.

The council won't accept anything else because OS maps are the only mapping data accurate and standardised enough for planning assessments. A planning officer needs to see exactly where your property sits relative to roads, boundaries, and neighbouring buildings, at a consistent and verifiable scale.

Location plan (1:1250 or 1:2500 scale)

This shows your property in the context of the surrounding area. Think of it as the "zoomed out" view. At 1:1250, an A4 sheet covers roughly 2 hectares of land. The planning officer uses this to identify your property, check access routes, and understand the neighbourhood context.

For standard residential properties in towns and suburbs, 1:1250 is the right scale. If you're in a rural area where your property sits on a larger plot, you may need 1:2500 to show enough surrounding context. Your council's validation checklist will tell you which they require.

Site plan or block plan (1:200 or 1:500 scale)

This is the "zoomed in" view showing your property boundaries, the existing building footprint, and the proposed extension. At 1:200, you can see individual dimensions and boundary distances. The planning officer uses this to check whether your extension sits within the plot boundaries and to assess its relationship with neighbouring properties.

For most householder applications, 1:500 gives enough detail. If your extension is close to a boundary or you need to show specific dimensions, 1:200 is better.

What Must Appear on Each Map

Both maps need specific elements, and missing any one of them will get your application bounced.

On the location plan:

• A red line boundary drawn around the entire application site, including the whole property and access from the public highway (the extension footprint alone is not enough)
• A north arrow
• A scale bar
• The OS copyright notice and licence number
• The date of purchase (maps must be reasonably current)

On the site plan:

• The existing building footprint
• The proposed extension, clearly distinguishable from the existing building
• Boundary lines with dimensions where relevant
• Adjacent buildings and structures
• Roads, footpaths, and any public rights of way
• Trees, if they're close to the proposed works
• Hard surfacing areas (driveways, patios)
• A north arrow and scale bar

Click to enlarge

Click to enlarge