Blog · 26 September 2026 · 3 min read
How to Read Your Water Meter in Portugal (and Use It to Find Leaks)
Short answer: the black numbers on the meter show cubic metres (m³) — that is what you pay for. The red numbers or small dials show litres. To check for a leak, close every tap and watch the small dial or red star: if it turns while nothing is using water, you have a leak.
Where to find the meter
In Lisbon flats the meter is usually in a cupboard on the landing, often grouped with the neighbours' meters, or in a cabinet at the building entrance. In some flats it is inside, near the kitchen or bathroom. In houses it is typically in a box on the outside wall or in the pavement.
Each meter has a number. Your water bill shows it, so you can find yours among several.
Reading the numbers
Black digits: whole cubic metres. One cubic metre is 1,000 litres. This is the reading the water company uses.
Red digits or small dials: fractions of a cubic metre — hundreds, tens and single litres.
Some newer meters are digital or read remotely; the display shows the total in m³ and may cycle through other information.
Sending your own readings
If the meter is not read regularly, you receive estimated bills, and later a correction. Most water companies — EPAL in Lisbon — let you submit readings online or by phone in a set window each month. It keeps the bills accurate and makes a leak show up sooner.
Using the meter to detect a leak
Close every tap and make sure no appliance is using water. Look at the small leak indicator (a small dial or a red star/triangle that spins). If it moves, water is flowing.
For slow leaks, write down the full reading including the red digits, wait an hour without using water, and read again.
Then isolate: close the valve on each toilet, then the water heater's inlet. If the meter stops when you close one, you have found where the leak is. If it keeps moving with everything closed, the leak is in the pipes. See signs of a hidden water leak.
The main valve next to the meter
Next to the meter there is usually a valve that shuts off water to your flat. Learn where it is now — in an emergency it is the first thing you need. See how to find your main water valve.
Do not tamper with the meter itself or its seals; it belongs to the water company.
Keeping a monthly log
Write down the reading on the same day each month — a note on your phone is enough. It shows your normal use, catches leaks early (a month that jumps for no reason), and lets you check your bills.
Winter and summer differences
Use rises with longer hot showers in winter, and with watering and extra showers in summer. Compare the same month year on year rather than month to month.
When the meter test says leak
Isolate toilets and the water heater first. If the meter still moves, the leak is in the pipes, usually hidden. Leak detection finds it before anything is opened — from 120 €.
Meter moving when nothing is on? We find hidden leaks before opening walls — from 120 €.
Hidden leak detectionFrequently asked questions
Which numbers do I send as my reading?
The black digits — whole cubic metres. The red ones are litres.
The meter moves slowly at night. Is that a leak?
If nothing is using water, yes. Even a slow leak adds up over months.
Can I move my water meter?
Only the water company can, and usually for a fee. Contact them.
My meter is broken or unreadable.
Report it to the water company; they replace faulty meters.
Is the meter my responsibility?
The meter belongs to the water company. Pipes after it, inside your flat, are yours.
Services Lisbon plumbing team
Guides written by the plumbers who do this work in Lisbon homes every week — drains, leaks, water heaters and pipework.
