Understanding your Octopus bill

An Octopus statement is easier to read once you separate three things: the energy you used, the payments you made and the running account balance.

That sounds obvious, but many confusing bills come from mixing those together. A statement can be accurate even when it does not match your monthly Direct Debit. It can also be worth querying even when the headline balance looks normal.

The quick check

Before reading every line, check these five points.

1. Does the billing period look right?
2. Are the opening meter readings close to the previous statement’s closing readings?
3. Are the latest readings marked actual, smart or customer read rather than estimated?
4. Do the meter serial number, MPAN or MPRN belong to your home if the bill looks wildly wrong?
5. Do the unit rates and standing charges match the tariff you think you are on?
6. Does the new balance make sense after charges, payments, credits and any previous balance are included?

If those checks pass, the statement is usually doing its job. If one fails, focus there before changing your payment amount or assuming Octopus has overcharged you.

Source check, 25 May 2026

The current source check for this page used Octopus’s statement questions page, Octopus’s statement-frequency help, Citizens Advice bill-check guidance and Ofgem back-billing rules. The practical points are:

• Octopus says connected smart-meter accounts should normally receive monthly statements from automatic readings. Non-smart accounts are more reading-led: if you submit readings, Octopus says it should send an up-to-date statement within a few days; if it does not receive readings, estimates can be used.
• Octopus still says a high charge can come from an incorrect submitted reading, several months of estimates being corrected, unusual usage, a meter problem or a calculation error. The first evidence check is the reading on the statement against the physical meter.
• Citizens Advice says estimated bills can be wrong and smart meters can still need manual readings when they are not working in smart mode. It also points readers to wrong-meter checks such as MPAN, MPRN and meter-reading comparisons.
• Ofgem’s back-billing rules still matter for old catch-up charges: in many domestic cases, suppliers cannot charge for energy used more than 12 months ago if the customer has not had an accurate bill or statement for it and has not behaved unreasonably.

The main numbers on an Octopus statement

Your statement is a snapshot for one billing period. It normally includes:

Line	What it means	What to check
Billing period	The dates the statement covers	It should line up with the meter readings used
Previous balance	The account balance brought forward from the last statement	Payments made after the last statement may appear separately
Energy charges	Standing charges plus usage charges for the period	Check both the rate and the kWh used
Payments	Direct Debits, card payments or other payments received during the period	These reduce the balance but are not the same as the energy charge
Credits or adjustments	Reversed charges, refunds, goodwill credits or corrected billing lines	Look for the explanation and the dates they cover
New balance	The account position after everything above is applied	Positive usually means credit. Negative means debit

The new balance is not simply this month’s usage. It is the previous balance plus new charges, minus payments and credits.

Charges, rates and VAT

Most Octopus bills are built from the same pieces.

Standing charge is the daily charge for having a gas or electricity connection. It is multiplied by the number of days in the billing period.

Unit rate is the price for each kilowatt hour of energy used. Flexible tariffs usually have one main unit rate for each fuel. Time-of-use tariffs such as Agile, Go, Intelligent Go, Cosy and Flux can show several usage lines because different time periods are billed at different prices.

Consumption is the number of kWh billed. For electricity, that usually follows directly from the meter reading difference. For gas, the meter records volume first, then the bill converts it into kWh.

VAT on domestic energy is charged at 5%. Octopus’s statement help notes that some bill views show unit rates before VAT while quotes and public tariff pages usually include VAT, so do not panic if a statement rate looks slightly lower than the advertised rate. Check whether VAT is being added later in the calculation.

Statement versus Direct Debit

This is the most common source of confusion.

Your statement shows what energy you used during the billing period and what that energy cost.

Your Direct Debit is a payment method. If it is a fixed monthly Direct Debit, it is designed to smooth expected annual costs across the year. It will not normally match the latest statement total.

For example, a £140 monthly payment and a £95 spring statement are not a mistake. The extra payment may simply be building credit for later. A £140 payment and a £220 winter statement are not automatically a problem either, if the balance was meant to be drawn down during colder months.

The account balance is where those differences meet. If the balance keeps moving in the wrong direction, check readings, tariff changes and the Balance Forecast before deciding what to change.

Estimated, smart and customer readings

Octopus says connected smart-meter accounts should usually be billed automatically each month from actual readings. If the connection is working, the statement should not rely on estimates.

Traditional meters, patchy smart meters or newly switched accounts can be different. If Octopus does not have a reliable reading, the statement may use an estimate. That estimate can be too high or too low. Citizens Advice gives the same broad warning: if a smart meter is not working in smart mode, you may still need to read the meter and submit readings until the data flow is fixed.

When a real reading arrives later, Octopus can correct the account:

• if the estimate was too high, you may see a credit or reversed charge
• if the estimate was too low, you may see a catch-up charge
• if only one fuel has a valid reading, you may get a statement for electricity or gas before the other fuel is ready

If a bill suddenly jumps, compare the meter readings on the statement with the meter itself. A digit too many, a missing register on a two-rate meter or a stale smart reading can explain a lot. If the numbers are completely implausible, also check that the meter serial number, electricity MPAN or gas MPRN belongs to your property rather than a neighbour or old meter record.

Why a bill can show credits, reversals or odd date order

A corrected Octopus bill can look messier than a normal one because the system may need to undo an old charge before adding the right one.

That is why you might see wording such as reversed account charge, credit, adjustment or a charge line for an older period. It does not always mean money has been taken twice. Sometimes it means Octopus has removed an earlier estimate and rebuilt the bill with better readings.

Dates can also appear out of order when Octopus fills a past billing gap. The important check is whether the final set of readings, rates and period dates make sense after the correction.

If the catch-up charge reaches back more than 12 months, pause before paying it without question. Ofgem’s back-billing rules can protect domestic customers from being charged for older energy where they have not previously had an accurate bill or statement for it and have not blocked the supplier from billing properly. Ask Octopus to split the calculation by period and explain which dates it believes are still recoverable.

First bills after switching

Your first Octopus statement can look unusual because the switch date rarely lines up perfectly with your preferred billing day.

Octopus may also be waiting for handover readings from your old supplier. That industry process can take several weeks, and electricity and gas may not complete at the same time. A first statement for only one fuel is annoying, but it does not automatically mean the other fuel has been lost.

Once opening readings are agreed and both fuels are flowing normally, later statements should settle into a more predictable rhythm.

Gas conversion in plain English

Gas meters do not usually measure kWh directly. They measure gas volume in cubic metres or, on some older meters, cubic feet. The bill converts that volume into kWh using an industry formula with a calorific value and volume correction factor.

You do not need to recalculate every line unless something looks wrong. The useful checks are simpler: make sure the meter type is right, the opening and closing readings are plausible, and the converted kWh is in the right ballpark for the period.

When to contact Octopus

It is worth asking Octopus to check the statement if:

• the reading on the statement does not match the meter
• a smart meter has stopped sending readings and bills are being estimated
• a first bill is still missing one fuel after the handover window has passed
• an old billing gap has produced a large catch-up charge you do not understand
• the tariff rates look wrong for your region, meter type or payment method
• the meter serial number, MPAN or MPRN does not match your property records
• a catch-up bill appears to include energy from more than 12 months ago
• the account balance keeps moving into debit despite current readings and a sensible Direct Debit

Send a clear note with the statement date, the readings you can see now and what looks wrong. Include meter photos and, for wrong-meter concerns, the serial number plus MPAN or MPRN evidence. For meter-exchange or missing-reading cases, the wrong-bill evidence checklist sets out the serial numbers, old and new readings, photos and corrected-bill details to gather before escalating.

A calm monthly routine

Once a month, especially if you are not on a reliably connected smart meter, do this before reacting to the headline balance.

1. Submit or confirm both gas and electricity readings.
2. Open the newest statement and check whether it used those readings.
3. Check any tariff-rate or payment-method change that happened during the period.
4. Compare the new balance with the Direct Debit guide and Balance Forecast.
5. If you decide Octopus still looks right for your home, keep the referral-code step separate from bill troubleshooting so you do not rush a switching decision while sorting an old account issue.

A good statement should leave you able to explain the balance in one sentence: previous balance, plus energy charges, minus payments and credits. If you cannot do that after checking the readings, the bill is worth querying.