How Much Does an Earthing Study Cost in the UK?

Almost nobody in this industry publishes prices, which makes budgeting an earthing study harder than it should be. Here are honest, indicative ranges for what earthing studies typically cost from a lean specialist consultancy in 2026 — and what makes a project sit at the top or bottom of each range. Every project is different, so treat these as budgeting figures and ask us for a fixed quote when you have site details.

Typical Price Ranges (2026)

• Simple single-site study — e.g. a small 11 kV substation or package substation with good input data already available: typically £1,500 – £3,000.
• Standard DNO connection / substation study — including fault current distribution, touch and step voltage assessment and mitigation design to BS EN 50522 and ENA TS 41-24: typically £2,500 – £5,000.
• Complex sites — EHV systems, rail traction and bonding interfaces, multiple interacting electrode systems, or EMI/transferred potential studies involving third-party infrastructure: typically £5,000 – £15,000+, scoped individually.
• Soil resistivity survey (fieldwork, where you don't already have data) — usually arranged separately: typically £1,000 – £2,500 depending on site size and location.

For comparison, large multidisciplinary consultancies commonly quote two to three times these figures for the same deliverable — you're paying for their overhead, not a better study.

What Drives the Price

Input data quality is the biggest factor. If you already have a soil resistivity survey, the DNO's fault level and clearance time, and a current site layout, the study is design work only and sits at the bottom of the range. Missing data means survey coordination, DNO correspondence and assumptions that later need revisiting.

Site complexity is the second factor. A single electrode system in uniform soil is quick to model. Multiple bonded systems, rails, pipelines or telecoms nearby, high fault levels, or poor (high-resistivity) ground all add modelling and mitigation iterations — each iteration is engineering time.

The approval route matters too. A study going to a DNO follows a well-trodden format. Studies for rail principal contractors or National Grid interfaces carry heavier assurance and documentation requirements, which adds time.

How Long Does It Take?

A single-site study with complete input data typically takes one to two weeks. Complex or multi-site studies take longer and we confirm the programme before starting. If your project has a DNO submission deadline, say so at enquiry stage — it's usually the critical path.

What About Cable Calculations and Lighting Design?

The same "nobody publishes prices" problem applies, so for completeness: ProDesign cable calculation packs typically run £300 – £600 for a single distribution board and £1,500 – £5,000 for a full building or multi-board network with protection coordination. DIALux lighting calculations start around £250 for a single area and typically £1,000 – £3,000 for a whole building including emergency lighting.

Getting an Accurate Quote

Send us the site layout, what the project is (new connection, substation, generation site, rail works), whatever data you already hold (soil survey, DNO fault data), and the deadline. We'll come back with a fixed price and a delivery date — usually within one working day.

Want the technical background first? Read What Is Earth Potential Rise (EPR)? or see the full earthing study design service.