What is the Community Infrastructure Levy (CIL)?

CIL is a charge that local authorities can set on new development to fund infrastructure (roads, schools, parks). It is charged per square metre of new floor space at rates set by each council in their CIL charging schedule. Rates vary significantly — from £0 in some areas to over £300/m² in parts of London. CIL replaced much of the infrastructure element of Section 106.

What is a Section 106 agreement?

Section 106 (of the Town and Country Planning Act 1990) agreements are legal obligations negotiated between developers and local authorities as a condition of planning permission. They typically cover affordable housing provision, education contributions, healthcare infrastructure, open space, and other site-specific requirements that cannot be addressed through CIL.

When is affordable housing required?

In England, affordable housing contributions are typically required on developments of 10 or more dwellings (or sites of 0.5 hectares or more). The percentage varies by local authority — typically 20-40% of units. In rural areas, a lower threshold of 5 units may apply. Some councils accept financial contributions in lieu of on-site provision for smaller schemes.

How much are education contributions per dwelling?

Education contributions under Section 106 typically range from £3,000 to £8,000 per dwelling, depending on the local authority and the number of bedrooms. Larger family homes attract higher contributions as they are more likely to house school-age children. Some councils exempt 1-bed units from education contributions. London boroughs tend to charge the highest rates.

Can CIL and Section 106 apply to the same development?

Yes, both can apply. CIL is a fixed charge on floor area that funds general infrastructure. Section 106 covers site-specific requirements not addressed by CIL, primarily affordable housing, and specific local needs. Since the 2019 CIL reforms, Section 106 can no longer be used for infrastructure items that CIL is intended to fund, to avoid double-charging.

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Section 106 / CIL Estimator

Estimate Community Infrastructure Levy (CIL) and Section 106 contributions including affordable housing, education, NHS and open space by region.

Number of Dwellings

Total homes in the development

Total New Floor Area

Gross internal area of new build

Region

Affects CIL rate and S106 levels

Affordable Housing %

Local policy requirement (typically 20-40%)

Include education contribution

Per-dwelling contribution to schools

Include NHS/healthcare contribution

GP and primary care contributions

Include open space contribution

Parks and play areas

How We Calculate This

This estimator calculates the Community Infrastructure Levy based on floor area and regional CIL rates, plus typical Section 106 contributions for education, NHS, open space and affordable housing.

The formula

CIL = Total floor area × CIL rate (£/m²)
Affordable units = Dwellings × Affordable %
S106 = Education + NHS + Open space per dwelling
Total = CIL + S106 contributions

For a 10-dwelling scheme at 100m² each in the South East: CIL = 1,000m² × £150 = £150,000. S106: education £50,000 + NHS £12,000 + open space £20,000 = £82,000. Total: £232,000 or £23,200 per dwelling.

Regional variations

London: CIL £150-£400/m², S106 highest in the country
South East: CIL £100-£200/m², moderate S106
Midlands/North: CIL £30-£100/m², lower S106
Always check your council's CIL charging schedule

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.