Water bill: how to read every line and spot the wrong charge
A water bill has four blocks: connection details, metering, billing and history. See what each line means, how to work out consumption, how the tariff works by category, billing units and bands, and which errors show up most on a company's bill.
By T&D Sustentável 10 min read
In this article · 7
To read a water bill, check four blocks: the connection details (account number, category and number of billing units), the metering (readings, days and consumption), the billing (consumption bands, water and sewage) and the history. Most wrong charges sit in three places: estimated readings, the number of billing units and the category of use. With your latest bill in hand, this guide shows what each line means and what to do when something does not add up.
In short:
- A water bill has four blocks: connection, metering, billing and history.
- The month’s consumption is the current reading minus the previous one, in m³. Compare the daily average, not the amount.
- Category and number of billing units set the price of each cubic metre and the minimum charge. An error there weighs every month without looking like an error.
- Brazil’s Sanitation Law provides for billing by user category, increasing consumption bands and a minimum quantity, which is why a few extra m³ can cost a lot.
- Billed consumption can differ from metered consumption: the minimum per billing unit, an estimated reading and the adjustment of an estimate explain the gap.
What lines are on a water bill?
Each water utility designs its own bill, but the information is almost always the same. The name of the line changes; its job does not.
| Line | What it is | What to check |
|---|---|---|
| Account, connection or property number | The property’s identity in the utility’s register | That it matches the right address, especially when the company has several sites |
| Reference | The month and year the bill covers | That no month is repeated or skipped |
| Customer details | Name or company name and billing address | That they are up to date, so notices and bills arrive |
| Water meter number | The meter installed at the property | That it is the same number engraved on the device |
| Previous and current readings, with dates | The figures on the dial at the meter reader’s two visits | The difference is the consumption; photograph the dial |
| Days of consumption | The interval between the two readings | Longer cycles add up more consumption |
| Type of reading | Actual or estimated, from the average | Repeated estimated readings call for an actual reading |
| Metered and billed consumption, in mÂł | What the meter recorded and what was charged | If they differ, why: minimum charge, average or adjustment |
| Category | Residential, commercial, industrial or public | That it matches the property’s real use |
| Billing units | How many units the same connection serves | That the number matches reality |
| Billing | The consumption bands, the tariff for each band and the water and sewage amounts | Which band consumption fell into and whether there is sewage service at the address |
| History | Consumption over the last months | An isolated jump, a gradual rise or a month out of pattern |
| Other entries | One-off services, instalments, interest and late-payment fines | That every item has a known origin |
How do you work out the consumption on a water bill?
Four simple calculations tell you whether the consumption charged makes sense:
- Consumption for the period: current reading minus previous reading, in cubic metres. Each mÂł is 1,000 litres.
- Daily average: divide consumption by the days in the period. It is the only fair comparison between months with different cycles.
- Comparison with history: put the daily average next to that of previous months, which the bill itself usually shows.
- Metered against billed: if the consumption charged differs from the metered one, find the reason. It may be the minimum per billing unit, an estimated reading or the adjustment of an earlier estimate.
Example: a previous reading of 1,250 and a current one of 1,310 give 60 mÂł. Over a 30-day period, that is 2 mÂł a day, or 2,000 litres. If the previous month averaged 1.5 mÂł a day, consumption rose by a third, and the question becomes why.
Consumption that rises with no change in routine has one main suspect: a leak. See hidden water leak: 7 signs and how to find it and, for the other causes, my water bill went up: 8 causes and how to cut it.
How does the water tariff work?
The tariff is not a single price per cubic metre. Brazil’s Sanitation Law, Law No. 11,445/2007, requires the billing structure to consider, among other factors, user categories spread over increasing consumption bands, a minimum consumption quantity and the minimum cost of keeping the service available (art. 30). In practice, four items set what a company’s water costs:
| Item | How it weighs on the bill | What to check |
|---|---|---|
| Category of use | Each category has its own table, and commercial and industrial users usually pay more per mÂł than residential ones | That the category matches real use, with documents |
| Consumption bands | The m³ gets more expensive as consumption rises; a few extra m³ push part of the volume into the next band | Which band the month’s consumption fell into |
| Minimum per billing unit | Many utilities charge a minimum consumption per billing unit, even if the property uses less | How many billing units are registered and whether each one exists |
| Sewage | Charged separately, in many cities calculated on the water volume | Whether there is sewage collection at the address and how it is calculated |
The item that misleads most is the number of billing units, because the error runs both ways. With fewer billing units than reality, consumption piles into the most expensive bands of the table; with more, the added-up minimum exceeds real consumption, and the company pays for cubic metres it did not use. In both cases the bill looks normal, month after month.
Correcting the classification is the job of T&D’s Water tariff consulting: it checks category, billing units and the utility’s regulations and runs the process from opening to the new tariff taking effect. The savings come from the billing, without changing the operation’s consumption, and the preliminary analysis starts with a recent invoice.
Which errors show up most on a water bill?
Seven errors account for most disputes. For each one, what to do:
1. Repeated estimated readings
When the meter reader cannot reach the meter, the utility bills by the average and adjusts later. Several months of estimates in a row build up a difference, and the adjustment arrives high. Make sure the meter is accessible and ask for an actual reading.
2. A wrong reading
The figure noted does not match the dial. Photograph the meter with the date and time and ask for a new reading.
3. A longer period than usual
A longer reading cycle adds more days of consumption. There is no reading error, but the comparison is only fair by the daily average.
4. The wrong category
The property is registered in a category that does not match its use, and the cubic metre costs more every month. The correction requires documents proving the real use.
5. The wrong number of billing units
Too many or too few, the error changes the minimum charge and the band consumption falls into. It is common in warehouses, residential buildings, office blocks and properties that changed use.
6. Sewage charged where there is no service
The sewage charge presupposes the service. If the address has no collection, or if the calculation method does not follow the regulations, the charge can be challenged.
7. A meter or entry that is not yours
A meter number different from the one installed, another property’s account number, a one-off service nobody asked for. Ask for each entry to be itemised.
Found one of these errors? The review request, the ombudsman, the regulatory agency and the double refund provided for in Brazil’s Consumer Protection Code are in the step by step on how to dispute the water bill.
How do you track the water bill every month?
A simple spreadsheet, filled in with every bill, turns the invoice into an indicator:
- month, days of consumption, readings and consumption in mÂł, copied from the bill;
- daily average and the change against the previous month and the same month last year;
- type of reading, actual or estimated;
- water and sewage amounts, separated, and the band consumption fell into;
- notes: building works, a shift change, a repaired leak, a supply cut in the neighbourhood.
With several sites, consolidate them all in the same spreadsheet and compare by the operation’s indicator, such as consumption per bed, per student or per meal. And read the meter yourself in the week of the utility’s reading: if the figures do not match, you find out before the bill. Telemetry takes that reading on its own, hour by hour, as remote water consumption monitoring shows. The full reduction programme is in the guide to water savings for businesses.
Frequently asked questions
What is billed consumption on a water bill?
It is the volume the utility charged for the month. It can differ from metered consumption, which is the difference between the readings: when the reading was estimated, when consumption fell below the minimum per billing unit, or when the bill carries the adjustment of an earlier estimate.
What are billing units on a water bill?
They are the units served by the same connection: each flat, shop, office or industrial unit supplied through the same meter. In Brazil they are called «economias». The number of billing units changes the minimum charge and how consumption spreads across the tariff bands, so it must match reality.
Why does sewage come on the same bill as water?
Because the same utility usually provides both services, and Brazil’s Sanitation Law allows tariffs to be set for each service or for both together. In many cities, sewage is calculated on the water volume. The charge presupposes that the service exists at the address.
Where is the meter number on the water bill?
Usually in the connection block or the metering block, near the readings. Check that it is the same number engraved on the meter itself: a different number means a mixed-up registration, and the bill may be metering another property. In that case, ask the utility for the correction with a photo of the device.
Can the utility charge a minimum consumption?
It can. Brazil’s Sanitation Law provides that the billing structure considers a minimum consumption quantity and the minimum cost of keeping the service available. The minimum is usually charged per billing unit, which is why a wrong number of billing units weighs so much.
Sources
- Law No. 11,445 of 5 January 2007, arts. 29 and 30, in Portuguese: billing per service or jointly, user categories, increasing consumption bands, minimum quantity and minimum availability cost
- Brazil’s Consumer Protection Code, Law No. 8,078/1990, art. 42, in Portuguese
- T&D Water tariff consulting: review of category, billing units and classification, with a preliminary analysis from a recent invoice
