Testing your borehole or well water in the UK: what to order, how to sample, what it costs
If your well, spring or borehole serves only your own home, nobody tests it for you: the council must assess and sample it only if you ask, and you pay [1]. Judge the results against the Private Water Supplies Regulations: no E. coli in 100 ml, nitrate up to 50 mg/l [2], iron up to 200 µg/l [3]. A laboratory test costs roughly £150–300 (approximate, as of September 2026) [4] [5].
Updated 2026-09-29 · every regulation and price links to its source at the bottom of the page. A guide, not a construction design.
Is testing a private water supply compulsory?
For a single dwelling with no business use, the English regulations do not require routine testing. The council steps in on request: “In the case of any other supply provided to a single dwelling, a local authority must carry out a risk assessment if requested to do so by the owner or occupier of that dwelling.” [1] It may charge the reasonable cost; the old fee caps were removed in 2018, so prices vary between councils [6].
Registering a private supply with the council is not a legal requirement, but the Drinking Water Inspectorate strongly advises it, and a new supply must not be brought into use until the council is satisfied it is not a danger to health [7]. Wales and Scotland have their own private supply regulations; the limits on this page are taken from the English text.
What should you test borehole water for?
Ask for a package that covers safety and the parameters you need to choose treatment. Limits are from the Private Water Supplies (England) Regulations 2016.
| Parameter | Limit | Why it matters |
|---|---|---|
| E. coli, enterococci | 0 per 100 ml [2] | Faecal contamination from septic tanks or livestock |
| Coliform bacteria | 0 per 100 ml, indicator [9] | Surface water getting into the source |
| Nitrate, nitrite | 50 mg/l and 0.5 mg/l; nitrate ÷ 50 + nitrite ÷ 3 ≤ 1 [2] | Fertiliser or sewage |
| Iron, manganese | 200 µg/l and 50 µg/l [3] | Staining; choice of iron filter |
| Hardness | No legal limit [10] | Scale; softener sizing |
| Conductivity | 2,500 µS/cm at 20 °C [9] | Total mineral content |
| pH, ammonium | 6.5–9.5; 0.5 mg/l [9] | Corrosion, pollution, filter choice |
| Chloride, sulphate | 250 mg/l each [9] | Taste, corrosion |
| Sodium | 200 mg/l [3] | Matters if you add a softener |
| Turbidity, colour | 4 NTU; 20 mg/l Pt/Co [3] | UV only works in clear water |
| Arsenic, lead, fluoride | 10 µg/l; 10 µg/l; 1.5 mg/l [2] | Health |
| Radon | 100 Bq/l [2] | Health |
Choose water treatment from your test →
Who can analyse the sample?
Samples taken for the council must be collected, transported and analysed by an organisation accredited by UKAS to ISO/IEC 17025 under the DWTS drinking water scheme. The Drinking Water Inspectorate publishes a list, the UKAS directory helps you find one nearby, and water company laboratories also take private samples [11].
If you order privately, check which tests the accreditation covers. One laboratory states that only its E. coli analysis is accredited for drinking water [12], and self-sampling kits do not always say whether their tests are accredited [4]. A kit is fine for choosing a filter; for a dispute or a house sale, use an accredited laboratory.
How do you take a water sample from a borehole?
We found no UK rule for owners taking their own sample, so follow your laboratory’s instructions. Good practice published by the Polish sanitary inspectorate [13]:
- Use the laboratory’s own bottles.
- Run the water until its temperature noticeably changes, so you sample the borehole rather than the pipes.
- Get the sample to the laboratory within 4 hours, ideally in a cool box.
- You are responsible for a correct sample; if in doubt, ask the laboratory or the council to take it.
What if the results are over the limits?
Indicator parameters such as coliforms, conductivity or chloride are warning signs to investigate; E. coli, enterococci or nitrate above the limit mean the water is not fit to drink as it is. Stop drinking it untreated, find the cause (a nearby septic tank, a damaged borehole head, surface water getting in) and choose treatment from the full analysis.
For a private supply the Drinking Water Inspectorate advises treating the whole supply rather than fitting a filter under one tap [15]. Bacteria are usually dealt with by UV at a dose of about 40 mJ/cm² or more, which only works in clear water with iron and manganese already reduced [16].
How much does a water test cost in the UK?
Our suggestion for choosing treatment: a chemical package with iron, manganese, hardness, pH, conductivity, chloride, sulphate, sodium and nitrate, plus a separate microbiology test.
| Option | Price (approximate, as of September 2026) |
|---|---|
| Council sampling and analysis, one council’s 2026 fees | £40 administration + £99 visit + £31.19 analysis, about £170 [17] |
| Self-sampling laboratory kit | 12 parameters £180, 27 parameters £294, including VAT [4] |
| Quick coliform test | £12.99 [4] |
| Laboratory microbiology (E. coli, coliforms, total viable count) | £82.68 ex VAT [12] |
| Laboratory chemical potability | £227.90–259.70 ex VAT [12] |
| Metals, including heavy metals | £206.70 ex VAT [12] |
| UKAS-accredited laboratory, 30+ parameters | From £250 ex VAT, results in 10–14 days (price published in 2024) [5] |
Choose water treatment from your test →
Frequently asked questions
Do I have to test my private water supply?
Not routinely for a single home in England; the council will assess and sample it if you ask, at your cost [1].
Can the council test my well water?
Yes, on request. It charges the reasonable cost, which varies by council [6]; one council’s 2026 fees add up to about £170 [17].
Which laboratory should I use?
One accredited by UKAS to ISO/IEC 17025 for drinking water (DWTS), for the tests you need [11].
Is there a legal limit for water hardness in the UK?
No. The regulations set no standard for hardness, calcium or magnesium [10].
Do I need to register my borehole?
Not by law, but the Drinking Water Inspectorate strongly advises it [7].
Sources
- The Private Water Supplies (England) Regulations 2016 (SI 2016/618), reg. 6(2)–(3), reg. 10(3), 10(8), reg. 21 + Schedule 5 (UK) · regulation · checked 2026-09-29 · source
- The Private Water Supplies (England) Regulations 2016 (SI 2016/618), Schedule 1, Part 1, Tables A–B; reg. 4(c); Table D (UK) · regulation · checked 2026-09-29 · source
- The Private Water Supplies (England) Regulations 2016 (SI 2016/618), Schedule 1, Part 1, Table B, Part II (national requirements) (UK) · regulation · checked 2026-09-29 · source
- Watersafe UK — Well water & borehole water testing kits (UK) · price · checked 2026-09-29 · ~ · source
- Springbore — Water testing of private water supplies, UKAS accredited water analysis (UK) · price · checked 2026-09-29 · ✓ · source
- The Private Water Supplies (England) Regulations 2016 (SI 2016/618), as amended by SI 2018/707 (UK) · regulation · checked 2026-09-29 · source
- Drinking Water Inspectorate — Registration of private water supplies, Registration (UK) · recommendation · checked 2026-09-29 · source
- mygov.scot — Apply for a private water supply grant; The Private Water Supplies (Grants) (Scotland) Regulations 2006, Grant (UK) · regulation · checked 2026-09-29 · ? · source
- The Private Water Supplies (England) Regulations 2016 (SI 2016/618), Schedule 1, Part 2, Table C (indicator parameters) (UK) · regulation · checked 2026-09-29 · source
- Drinking Water Inspectorate — Private water supplies treatment guide: The physical and chemical properties of water, Hardness, Table 1 (UK) · recommendation · checked 2026-09-29 · source
- Drinking Water Inspectorate — Private water supplies: Analytical services (Information letter 05/2013), Analytical Services (UK) · regulation · checked 2026-09-29 · source
- Feedwater — What are the rules for testing private water supplies (UK) · price · checked 2026-09-29 · ✓ · source
- PSSE w Jaśle: «Pobieranie i transport próbek wody … (Badanie wody używanej dla własnych potrzeb)» (gov.pl), pkt 3–6 (PL) · recommendation · checked 2026-09-29 · ~ · source
- US EPA — Private Drinking Water Wells: Protect Your Home's Water, Testing frequency; Where to test your water (US) · recommendation · checked 2026-09-29 · source
- Drinking Water Inspectorate — Private water supplies treatment guide: Point of use treatment, Point of use treatment (UK) · recommendation · checked 2026-09-29 · source
- Drinking Water Inspectorate — Private water supplies: treatment guide, UV disinfection, UV disinfection (UK) · recommendation · checked 2026-09-29 · source
- West Suffolk Council — Private water supply (Fees and charging 2026), Fees and charging 2026 (UK) · price · checked 2026-09-29 · ✓ · source
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