How to Read an Electricity Meter, Including Two-Rate Meters

Reading an electricity meter comes down to one rule: write down the numbers from left to right and ignore the rest. On a standard single-rate meter that means the first five digits, with any red numbers or figures after a decimal point left out¹. On a two-rate meter, the kind used for Economy 7, there are two readings to take, one for the day or peak hours and one for the night or off-peak hours, and both must go to your supplier¹. Dial meters, electronic button meters and smart meters each display those numbers differently, but the underlying rule holds.

The reason it matters is billing. Your supplier needs regular readings to work out your bills and will estimate your usage if you do not send them¹. An estimate is a guess based on past use, and it can be too high or too low, which means paying too much or building up a debt. Taking the readings yourself, and knowing which register is which on a two-rate meter, keeps the bill tied to what the home actually used.

What your meter figures are measuring

An electricity meter records one thing: the total amount of electricity, in kilowatt hours, that has passed through it since it was installed. The number only ever goes up, and your supplier works out each bill by subtracting the previous reading from the new one. On most electricity meters there are five numbers before the decimal point², and electric dial meters have five digits to read where gas has four⁷.

Two identifiers sit alongside those numbers:

• MPAN: the Meter Point Administration Number, sometimes called the S number, identifies the electricity supply point itself and appears on both the bill and the meter⁸.
• Meter serial number: this identifies the physical meter, and you can use it to make sure you are being billed for the energy your home used and not a neighbour's⁹.

If a bill ever shows readings that do not match what the meter displays, the serial number is the first thing to compare.

A dial meter looks different from a digital one but records the same total. An electricity dial meter has five or more dials, each turning to point at a number between 0 and 9, and each turning in the opposite direction to the dials beside it¹. The dials are simply a mechanical way of showing the same five digits.

Digital meters: the first five digits, ignoring any in red

A single-rate digital meter shows five numbers, which may be followed by one or more numbers in red. Only the first five matter: note them down from left to right and ignore the red one¹⁰. The same rule appears across every guide: write down the first five numbers shown from left to right and ignore any others, including red numbers¹, take a reading of five black numbers from left to right ignoring any red numbers¹¹, and ignore the figures after the decimal point².

The red digit, or the digits after the decimal point, records tenths and hundredths of a unit. Suppliers bill in whole units, so those small figures are never wanted. Some meters show the fraction marked 1/10 or 1/100 instead of printing it in red; the instruction is the same, read from left to right and ignore those numbers¹².

A single-rate meter means exactly one reading and one flat unit rate for every hour of the day¹³. If the supplier's website or app asks for one electricity reading, that is the confirmation: the meter is single-rate and the five digits are all it needs. If it asks for two, the meter is two-rate and the next sections apply.

Reading a dial meter from left to right

Dial meters are older and slower to read, but the method is fixed. Read the first five dials from left to right, ignoring any red dials or dials marked 1/10¹. Start with the dial on the left and write down the number the pointer has just gone past, not the number it is heading towards¹³. Dials without numbers or hands should be disregarded altogether².

The two awkward cases are when a pointer sits between two numbers and when it sits directly over a number:

• Between two numbers: write down the lower one. Between 9 and 0, write down 9, because the dial has not yet completed its turn¹.
• Directly over a number: check the dial to its right. If that pointer has passed zero, the number stands; if it is still working round between 9 and 0, reduce the figure by one¹.

Because each dial turns in the opposite direction to its neighbours, it is easy to misread a pointer as being closer to the next number than it is. Reading the dials in order, left to right, and checking each pointer against the dial beside it is what keeps the reading honest¹⁴. A dial reading that comes out lower than the previous bill's reading is a sign one dial has been misread.

Getting a reading from an electronic meter

Electronic meters, including smart meters, keep the same numbers behind a screen and bring them up with a button. The layout varies by model, so the practical approach is to find the button or buttons and press until a number followed by kWh appears. The common layouts are:

On a keypad meter, press 9, or A on meters with A and B buttons, until the screen flashes or shows IMP or IMPORT with a number followed by kWh¹². The word import matters: it is the electricity coming into the home, which is the figure a bill is built on. A reading can always be taken from a smart meter by hand, whether or not it is sending readings automatically¹⁶.

Two-rate meters: note down both figures each time

A two-rate meter exists because the home is on a tariff with two prices: one for daytime use and one for night-time use¹⁷. The meter therefore has two registers, and both readings have to be submitted every time. On the common two-row layout, the top row is labelled low or night and the bottom row is labelled normal or day¹. Read both rows, write the numbers left to right, and ignore any numbers shown in red¹.

The labels are not always intuitive, and one trips people up regularly:

• If there is an N on the label it stands for normal, not night¹.
• The night-time or off-peak reading is the one marked low or night¹⁸.
• On some meters the registers appear as Rate 1 and Rate 2, or R1 and R2, with one register for on-peak hours marked normal or day and one for off-peak hours marked low or night¹⁹.

A dual rate meter simply records different rates at different times of day, for example a higher rate at breakfast and teatime and a lower rate overnight²⁰. Which register is which can vary between meters, so the safe check is the bill: it names the registers it expects, and the readings can be matched to them. Sending only one of the two readings leaves the supplier to estimate the other, which defeats the purpose of reading the meter at all.

Both readings from a two-rate meter with one display

Not every two-rate meter has two rows. Some have only one digital display, which either flashes the different rate readings in a cycle or has a button that makes the display switch between them¹. The display shows only one rate at a time, and the readings may switch automatically or need the button¹⁷. Either way, the job is to wait or press until both numbers have appeared, and write down the numbers shown left to right for each reading, making sure both are captured¹.

On Northern Ireland Networks dual and multi-rate meters, push the button to scroll through the display: Rate 1 or R1 gives the first read, Rate 2 or R2 the second, and TOTAL B shows heating units on a multirate meter²¹. On the same network's keypad meters, push 3 for the first read and push 3 again for the second or additional reads¹⁴.

For homes with renewable technology installed, an import and export meter uses a blue button. Press it repeatedly until a small 2 appears in the corner of the display for the low, night rate reading²². The same button repeated brings up a small 5 followed by five numbers, which are the export reading, the electricity sent back out²².

Spotting whether an Economy 7 meter has two rates

The clearest sign of a two-rate meter is on the bill rather than the meter: electricity unit rates are either a single rate or a dual rate, and a dual rate provides two meter readings, usually called Economy 7²³. If you get cheaper electricity at certain times, you might have a two-rate meter¹. Economy 7 requires a special multi-rate meter to be installed at the home²⁴, and these economy tariffs relate to a type of meter with two distinct electricity rates²⁵.

On the meter itself, the signs are:

• Two meter readings, a low or off-peak rate and a normal, high or on-peak rate, or a button to press to see each rate on an electronic meter³.
• Digital and prepayment Economy 7 meters include two different readings, usually accessed by pressing a button, sometimes marked Rate 1 and Rate 2².
• Some meters show a number marked day rate alongside a red button that you push to get the night rate²⁶.
• The two sets of numbers are typically marked low and normal²⁷.

If the meter shows only one row of five digits and the supplier asks for one reading, it is a single-rate meter on a flat rate¹³. If in doubt, the supplier can confirm from the MPAN which meter type is installed at the address⁸.

The seven-hour off-peak period behind the two rates

Economy 7 charges two different prices for electricity depending on when it is used²⁸. The cheaper rate applies for seven hours, usually between midnight and 7am³, and at all other times electricity is charged at a more expensive peak rate³. The name comes from those seven hours of cheaper electricity overnight⁵.

The exact window is not fixed nationally. The cheaper period usually runs between midnight and 7am, but this varies across suppliers⁵, and the seven-hour period falls at some point between 11.00pm and 8.00am, defined by the regional network operator, the company responsible for physically supplying electricity to the property⁴. The remaining 17 hours of the day are charged at the higher rate²⁹. Some energy companies also offer extra hours during winter⁵, and some variations of the tariff offer 8.5 or 10 hours instead of seven³⁰.

Because Economy 7 has a cheap and a more expensive rate, it matters that the on-peak and off-peak hours are understood correctly¹⁹. The tariff is mainly intended for homes that run on an electric heating system and use storage heaters²⁷, and people with Economy 7 typically use the cheap hours to charge their storage heaters with heat³⁰. It is only available for electricity-heated homes and not those with a gas supply⁵. The arithmetic that decides whether it pays is covered in is Economy 7 worth it if I use electricity at night?.

White meter north of the border and the situation in Northern Ireland

In Scotland, Economy 7 meters are known as white meters, because the meters supplied by energy companies there were white³¹. White meters, usually found in Scotland, are commonly known as Economy 7 meters in England³². The naming extends further: some multi-rate meters are also called Heatwise meters, and in Scotland are often referred to as white meters³³.

The metering arrangement can differ too. A white meter uses two different meters showing two different readings, one for normal consumption and one for off-peak consumption³². The off-peak hours can also differ: while Economy 7 meters offer seven hours of off-peak rates, white meters offer eight hours³². Scottish households with more than two electricity readings, or with metering and billing they do not understand, are advised to seek help, because restricted metering arrangements are a Scottish issue⁶.

In Northern Ireland the network is separate, and the guidance comes from Northern Ireland Networks. Its meters follow the same patterns: push the button to scroll through the display, with Rate 1 or R1 for the first read and Rate 2 or R2 for the second²¹, and push 3 on the keypad for the first read and again for the second¹⁴. Import and export meters for homes with renewables use the blue button method described above²².

Economy 7 mode on smart meters

A smart meter measures the energy the home uses, records it, and sends the readings to the supplier automatically³². Some electricity smart meters show separate readings for day and night tariffs, Economy 7 pricing, and peak and off-peak usage¹⁵. You can get a smart meter if you are on an Economy 7 tariff, but not all suppliers can offer one⁴. Smart meters are compatible with Economy 7 tariffs and fixed rate tariffs, and can also enable newer time-of-use tariffs, allowing you to switch tariffs without changing the meter²⁷.

On a keypad meter, the reading is brought up the same way as on any other keypad meter: press 9, or A on meters with A and B buttons, until the screen shows IMP or IMPORT with a number followed by kWh¹². The word import matters: it is the electricity coming into the home, which is the figure a bill is built on. A reading can always be taken from a smart meter by hand, whether or not it is sending readings automatically¹⁶.

A smart meter should be in smart mode, sending regular readings to the supplier, and the sign that it is, is being able to see current energy use on the in-home display unit¹⁶. If a smart meter has gone into dumb mode, readings have to be taken manually and shared with the supplier³⁰. When it is working, the meter sends automatic readings monthly, weekly, daily or even half-hourly⁶, and households with a working smart meter do not need to submit readings themselves³².

Comparing your readings with your bill

Once the readings are taken, the bill is where they are checked. If you have an estimated read, the bill or statement will generally say estimated or show an e next to the reading, while a c or an a indicates a customer-supplied or actual reading¹⁸. An S next to a meter reading on a bill means the reading came directly from the smart meter³⁰.

Suppliers need regular readings to work out bills and will estimate usage if they do not receive them¹, and under Ofgem's monitoring of billing outcomes, estimated meter reads are not classed as accurate if they differ from actual consumption²⁸. Consumers also have the right to know how their bill is calculated³¹.

The check itself is simple: the reading on the bill should match or slightly precede the reading on the meter, and it should be higher than the previous bill's reading. If the bill's reading is lower than the meter's by a wide margin, the bill was estimated earlier in the period. If it is higher than the meter shows, the wrong meter may be being billed, and the serial number and MPAN are what to compare⁸. The process for sending readings is covered in how to submit meter readings, and a suspected fault in how to report a faulty or inaccurate meter.

Switching off a two-rate tariff and meter independence

Moving between tariff types is where the meter, not the tariff, can be the obstacle. If you do not already have an Economy 7 meter, your chosen supplier will need to install a new one⁴. A smart meter removes that friction: because it is compatible with Economy 7, single-rate and newer time-of-use tariffs, the tariff can change without the meter changing²⁷. Economy 7 itself remains on offer as a tariff from most energy suppliers⁴.

What the meter cannot do is set the price. Except by switching, you do not control the tariff your energy supplier sets, but you can change how much energy you use²⁹. A two-rate meter is a tool for shifting consumption into cheaper hours, and it only pays when enough electricity is genuinely used overnight: at least 40% of electricity used at night for the tariff to be economical, according to National Energy Action³, more than 40% according to Energy Helpline³³, more than 35% as Uswitch's rule of thumb⁴, and at least 30% according to Which?⁵.

The independence a household gains from reading its own meter is real but bounded. Accurate readings end dependence on the supplier's estimates, and a two-rate meter with storage heaters lets a home heat itself overnight at a lower unit price. What remains is the supplier, which sets both rates and can change them; the network operator, which defines the off-peak window⁴; and the meter itself, which is owned by the supplier and must match the tariff. Reading it correctly is the one part of that chain the householder controls outright, and the wider steps are set out in energy independence step by step and the home energy how-to guide.