Can I dispute a sudden spike in my water bill?

What causes a sudden spike in your water bill?

Several practical issues can cause a sudden increase in your water bill. These problems may arise from internal faults, operational changes, or billing errors. It’s best to consider each possibility carefully and rule them out one by one before contacting your supplier.

A hidden leak

This is one of the most common reasons for a sudden spike. Leaks often happen underground, inside walls, or under floors, where you may not notice any visible water damage. A cracked pipe, corroded joint, or failed seal can cause constant water loss without drawing attention. Even small leaks can waste thousands of litres over time, which can drive your bill up without any obvious sign. If your meter keeps running when no one is using water, this is usually the first thing to check.

Major business changes

If you’ve recently brought on new equipment, extended your business opening hours, or taken on additional staff, your water consumption may increase sharply in turn. Equipment like commercial dishwashers, washing systems, or cooling towers can all use significant amounts of water. What’s more, it could also be the result of seasonal changes in activity, which may increase usage during peak months. If your business has recently altered its operations in any way, that’s a good one ot consider before raising a dispute – it could save you a bit of time!

Faulty appliances

Things like toilets, taps, and urinals that aren’t shutting off properly (for whatever reason) can all waste huge volumes of water throughout the day. In many cases, it can be something like a malfunctioning flush valve or dripping tap that’s going unnoticed in a staff toilet or maintenance area. Automatic systems are especially vulnerable, as they may continue running even when no one is present. So, make sure to check all your appliances regularly, and listen for continuous water movement or unexpected noise.

Incorrect meter readings

Water companies rely on manual or estimated meter readings to calculate your bill. That means if the meter reader enters the figures incorrectly, or if the supplier bases your bill on an inaccurate estimate, the result may be a sudden and unjustified spike. Sometimes, it can be something as simple as a human error – although that doesn’t make it any less stressful! You can give yourself a bit of peace of mind by comparing the current meter reading to the one shown on your bill. If the figures don’t match, this could explain the issue.

Backdated charges or tariff changes

Some suppliers apply charges retroactively, especially if they haven’t been able to take a reading for several months. This can lead to a sudden adjustment that covers usage across several billing periods. A tariff change may also increase your costs without a corresponding increase in water use. If your supplier recently updated their rates or moved you to a different charging structure, check whether that accounts for the new amount.

Who to contact when you spot an issue

If you identify a possible problem with your bill, it’s best to report it directly to your water supplier. Most companies have a dedicated billing or customer care team that handles these queries. You can check your invoice for a customer contact number or visit the supplier’s website for their official complaints process. When you get in touch, you’ll need to tell them in detail about the issue and reference specific readings, dates, and any supporting data. It helps to explain how the current bill compares to your past usage and why the increase appears unjustified.

In some cases, your supplier may ask you to complete a written complaint form or send your query by email. Don’t forget to follow their instructions carefully, and retain copies of all correspondence. If your premises are managed by a facilities company or landlord, ideally they need to be notified them too. They may be responsible for maintaining the infrastructure and could help with tracing leaks or providing access to the meter. If you operate within a shared tenancy, clarify who holds the water account and ensure the named account holder makes the dispute directly.

What to include when raising a dispute

Your written dispute needs to present all the evidence you’ve collected, and obviously make sure to include your full account details, a clear explanation of the issue, and copies of recent bills. Your manual meter readings are also really important, so list those with the exact dates and times they were taken. If you can, attach photos of the meter, especially if the current reading differs from what appears on the bill. If you conducted any leak tests, describe the steps you followed and the results you observed. Finally, add notes about any known changes to your site operations or water usage patterns that might explain part of the increase. (Such as the business changes we mentioned earlier.)

If you’ve had any prior conversations or calls with the supplier, reference those too. If you’ve got the names of people you spoke to, mention those, as well as the the dates of those calls, and any case numbers they issued. If you requested a meter test or technician visit, it helps to state when this occurred and what was found. Where possible, you’ll also want to include statements from third parties such as landlords or engineers, especially if they’ve inspected the site or verified a fault. Essentially, the ultimate goal is to create a complete and chronological record that shows the problem, the actions you took, and the reason you believe the bill is inaccurate.

What will the water company do after you complain?

Once your water company receives your complaint, they will open a case and begin reviewing your file. A member of their billing or investigations team will check your usage history, compare recent meter readings, and examine any documents you submitted. If they find evidence of a leak, they may offer a leakage allowance, which reduces your charges for the affected period. Some suppliers apply this automatically, while others require a separate application. If they believe the meter is faulty, they may schedule a replacement or conduct a further test to verify accuracy.

If your complaint relates to a billing or clerical error, they’ll investigate their records and confirm whether an adjustment is needed. You may receive a revised bill, a refund, or an explanation of why the original amount stands. The company must provide a written response that outlines their findings and what action they will take. If you disagree with the outcome, you have a variety of options for escalation.

Alternatively, if the case is causing you particular stress or hardship with all the admin involved, you may just choose to simply pick your battles, as many business owners do. However, if you’re not happy with your water supplier’s handling of the issue, you may even decide to start switching water suppliers.

That’s exactly where we can help here at The Business Water Shop. With a network of trusted suppliers at our disposal that spans across the UK, we’re perfectly positioned to get you the most competitive water quotes for your business. In fact, we’re able to save some customers up to 55% on their water bills, and you can count on us to use all our resources and industry expertise to get you the best deal.

It only takes a few minutes to get your online quote – so if you’re thinking about switching business water suppliers, there’s never been a better time to do it!