Business energy bill explained: every charge and code on your invoice

Business energy bills contain considerably more information than most domestic bills.

Alongside your electricity or gas consumption, you may encounter meter identifiers, estimated readings, network costs, policy charges, Climate Change Levy, VAT and charges relating to your site’s electrical capacity.

Some of these costs appear as separate lines. Others are bundled into your unit rate or standing charge.

In simple terms, a business energy bill is normally calculated as:

Previous balance + energy used + standing charges + additional charges + CCL + VAT − payments and credits = amount due

However, the precise calculation depends on your contract, meter type and supplier. Ofgem lists wholesale energy, network costs, government schemes, taxes, metering, supplier costs and broker commission among the costs that can contribute to a business energy bill.

This guide explains what every common field means, how to check the calculations and what to do if something appears incorrect.

Rates and regulations last reviewed: 29 July 2026.

Business energy bill checklist

Before paying an invoice, check these seven details:

1. The supply address is correct.
2. The MPAN or MPRN matches the premises.
3. The meter serial number matches the physical meter.
4. The billing period does not overlap another invoice.
5. The meter readings are accurate rather than estimated.
6. The unit and standing-charge rates match your contract.
7. All payments, credits and agreed tax reductions have been applied.

A mistake in any one of these areas can produce an incorrect bill.

What appears on the first page?

The first page normally summarises your account and the amount you owe.

Bill field	What it means	What to check
Account number	The supplier’s reference for your account	Do not confuse it with a meter number
Invoice number	A unique reference for that particular bill	Quote this when raising a billing query
Invoice date	When the invoice was produced	This may also be the tax-point date
Billing period	The dates covered by the charges	Check for gaps or overlapping periods
Supply address	The premises receiving the energy	This can differ from the correspondence address
Previous balance	Money carried forward from an earlier invoice	Confirm it matches the previous closing balance
Payments received	Direct Debits or other payments credited	Check the dates and amounts against your bank account
Adjustments	Corrections, reversals or reconciliations	Ask for an explanation if the description is unclear
Amount due	The amount the supplier expects you to pay	Recalculate it from the detailed charge lines
Payment date	When the payment must reach the supplier	Late-payment charges may apply after this date
VAT number	The supplier’s VAT registration number	Required on a valid VAT invoice

An account can also show a credit balance. This means the supplier is holding more money than the account currently owes. It is not the same as a credit note, which is a document reversing or reducing a previous charge.

The main charges on a business energy bill

Most invoices contain some combination of the following costs.

Charge	Typical calculation
Electricity or gas consumption	kWh used × unit rate
Standing charge	Number of billable days × daily rate
Climate Change Levy	Taxable kWh × applicable CCL rate
Capacity charge	Agreed kVA × charge per kVA
Excess capacity	kVA above agreed capacity × excess rate
Reactive power	Chargeable kVArh × applicable rate
Metering and data services	Fixed monthly or daily fee
Pass-through costs	Actual network or policy costs
VAT	Applicable percentage of the taxable subtotal

A fully fixed contract may incorporate most non-commodity costs into the unit rate. A pass-through contract can show network and policy costs separately or reconcile them later.

The absence of a separate line does not necessarily mean you are avoiding that cost. It may already be included elsewhere in the tariff.

How an electricity bill is calculated

The basic electricity calculation has four stages.

1. Calculate the consumption

For a single-rate meter:

Consumption = closing reading − opening reading

If the opening reading is 120,000 and the closing reading is 130,000, the recorded consumption is 10,000 kWh.

Some larger meters use a multiplier:

Billable consumption = reading difference × meter multiplier

For example, a reading difference of 2,000 with a multiplier of five produces billable consumption of 10,000 kWh.

2. Apply the unit rate

Energy charge = consumption in kWh × unit rate

Unit rates are normally quoted in pence per kilowatt-hour. A rate of 22.50p/kWh is equivalent to £0.225/kWh.

3. Apply the standing charge

Standing-charge cost = daily standing charge × billable days

A standing charge of 100p per day is £1 per day. Over 30 days, it costs £30.

Read more about business energy standing charges.

4. Add taxes and other charges

CCL, capacity, metering and any separately itemised non-commodity charges are added before VAT is calculated.

Worked electricity bill example

Consider a business that uses 10,000 kWh over a 30-day billing period.

The contract rate is 22.50p/kWh, excluding CCL, and the standing charge is 100p per day.

Invoice item	Calculation	Cost
Electricity used	10,000 kWh × 22.50p	£2,250.00
Standing charge	30 days × £1.00	£30.00
CCL	10,000 kWh × 0.801p	£80.10
Subtotal before VAT		£2,360.10
VAT at 20%	£2,360.10 × 20%	£472.02
Total invoice		£2,832.12

This is an illustrative calculation, not a current market quotation. It assumes that the business pays the main CCL rate and standard-rate VAT.

Check whether a quoted unit price includes CCL before adding it. Otherwise, you could accidentally count the tax twice when estimating your costs.

Understanding multi-rate electricity meters

A multi-rate meter records electricity in two or more registers. These may be labelled:

• Day and night
• R1 and R2
• Rate 1 and Rate 2
• Normal and low
• Peak and off-peak
• Weekday and weekend

Each register can have a different unit price.

Suppose a business uses:

• 6,000 kWh at 24p/kWh
• 4,000 kWh at 18p/kWh

Its consumption charge would be:

(6,000 × £0.24) + (4,000 × £0.18) = £2,160

Do not assume that R1 is always the day register or R2 is always the night register. Labels and switching times vary. Compare the meter readings, invoice and contract schedule to confirm which rate applies.

What is an MPAN?

The Meter Point Administration Number identifies an electricity supply point. It is sometimes called a supply number or S-number.

The full MPAN is commonly displayed as 21 digits arranged in a box resembling a large letter S. The bottom 13 digits are known as the MPAN core and are usually the part requested when changing supplier or checking a supply.

The MPAN identifies the electricity connection—not the physical meter. It normally remains the same when the supplier changes or a meter is replaced.

A traditional MPAN display can contain:

MPAN section	Meaning
Profile class	Historically described the site’s consumption and settlement profile
Meter time-switch code	Describes the metering configuration
Line-loss factor class	Historically linked the supply to network-loss charging
MPAN core	The permanent 13-digit identifier for the supply point

The market-wide half-hourly settlement programme is changing some of the technical fields shown above the MPAN core. Therefore, older explanations of profile classes and line-loss codes may not match every newly migrated invoice. The 13-digit MPAN core remains the most useful identifier.

See our full guide to finding and understanding your MPAN.

What is a meter serial number?

The meter serial number, or MSN, identifies the physical meter installed at the premises.

It usually contains letters and numbers and should appear:

• On the front of the meter
• Beside the relevant readings on your invoice
• In the supplier’s online account

The meter serial number can change when a meter is replaced. The MPAN normally does not.

If the bill’s serial number does not match the meter, the supplier could be using readings from an old meter or billing the wrong supply.

Actual, customer and estimated readings

Suppliers use different codes, but common descriptions include:

Reading description	Meaning
Actual	Obtained by the supplier, meter operator or automated meter system
Customer	Submitted by the business or its representative
Estimated	Calculated because an acceptable reading was unavailable
Smart or remote	Collected automatically from a communicating meter
Change of meter	Reading taken when a meter was removed or installed

Letters such as A, C and E are commonly used, but they are not completely standardised. Always check the legend printed on the invoice.

Estimated readings can be too high or too low. A low estimate may appear beneficial initially, but the missing consumption will normally be charged when the account is reconciled to an actual reading.

What is the meter multiplier?

Some larger electricity sites use current transformers because the full electrical load is too high to pass directly through the meter.

The displayed reading may therefore represent only a proportion of the real consumption. A multiplier converts it into billable kWh.

For example:

• Meter difference: 2,500
• Multiplier: 20
• Billable consumption: 50,000 kWh

An incorrect multiplier can create a significant overcharge or undercharge. Check the invoice, meter exchange documents and metering records if consumption suddenly changes without an operational explanation.

Half-hourly electricity bill charges

A half-hourly meter records consumption in 30-minute periods. These invoices can contain charges not normally seen on a straightforward small-business bill.

Maximum demand

Maximum demand is the highest average level of electrical demand recorded during a settlement period. It is measured in kilowatts rather than kilowatt-hours.

• kW measures how quickly electricity is being used.
• kWh measures how much electricity is used over time.

A warehouse running several large motors simultaneously may have a high maximum demand even if its total monthly consumption is moderate.

Agreed capacity

Agreed capacity (also called maximum import capacity or authorised supply capacity) is the amount of electrical capacity reserved for the site. It is usually measured in kilovolt-amperes, or kVA.

A common calculation is:

Agreed capacity × daily kVA rate × days

The rate and calculation method depend on the distribution network and contract.

Excess capacity

If a site exceeds its agreed capacity, the invoice may include an excess-capacity charge. Excess capacity can cost more per kVA than the authorised capacity.

Repeated excess charges may indicate that:

• Equipment is starting simultaneously
• New machinery has increased site demand
• The agreed capacity is too low
• Demand is not being managed effectively
• Meter or network data requires investigation

Increasing agreed capacity can reduce excess charges, but it may increase the regular capacity charge. The site may also need an engineering assessment or network upgrade.

Reactive power

Some electrical equipment draws reactive power as well as useful active power. This is common with motors, compressors, refrigeration, welding equipment and older lighting systems.

Reactive energy may be measured in kVArh. A poor power factor means the network must carry more current to deliver the same useful output.

Possible remedies include:

• Power-factor correction equipment
• Modern variable-speed drives
• Correctly sized motors
• Improved equipment maintenance
• Replacing inefficient transformers or lighting

A specialist should assess the installation before changes are made.

Meter operation and data collection

A half-hourly invoice may contain fees for:

• Meter Operator, or MOP, services
• Data Collector, or DC, services
• Data Aggregator, or DA, services
• Communications equipment
• Meter maintenance

These services may be included in the energy contract or supplied under a separate agreement.

Worked half-hourly bill example

This illustrative site uses 20,000 kWh in 30 days and has 100kVA of agreed capacity.

Invoice item	Calculation	Cost
Electricity used	20,000 kWh × 22.50p	£4,500.00
Standing charge	30 days × £1.00	£30.00
CCL	20,000 kWh × 0.801p	£160.20
Capacity	100kVA × 30 days × 10p	£300.00
Reactive energy	1,000kVArh × 0.50p	£5.00
Meter and data services	Fixed fee	£25.00
Subtotal		£5,020.20
VAT at 20%		£1,004.04
Total invoice		£6,024.24

The capacity and reactive-power rates are hypothetical. Actual charges are site-, network- and contract-specific.

Network and policy costs explained

Ofgem identifies network costs, government schemes and supplier operating costs as components of business energy prices. These are often called non-commodity charges.

Abbreviation or term	What it pays for
DUoS	Use and maintenance of the local electricity distribution network
TNUoS	Use and maintenance of the high-voltage transmission system
BSUoS	Balancing the electricity system in real time
Distribution losses	Electricity lost while travelling through local networks
Transmission losses	Electricity lost through the transmission system
Capacity Market	Payments supporting sufficient electricity-generation capacity
Renewables Obligation	Support for qualifying renewable generation
Contracts for Difference	Support intended to provide low-carbon generators with revenue certainty
Feed-in Tariff	Costs associated with the historic small-scale generation scheme
AAHEDC	Assistance with high distribution costs in northern Scotland
Green Gas Levy	Funding connected with the Green Gas Support Scheme
REGO	Certificate costs associated with renewable electricity claims
Metering costs	Meter installation, operation, communications and data collection
Supplier costs	Billing, customer service, credit risk and account management
Broker commission	Payment to an intermediary, either separately or through the tariff

Further explanations are available in our guides to DUoS, TNUoS and BSUoS.

Fixed and pass-through contracts

With a fully fixed contract, most network and policy costs are incorporated into the agreed unit rate. This provides greater budget certainty, although taxes and certain exceptional adjustments may still be separate.

With a pass-through contract, selected costs are charged at the prevailing rate. Your invoice may contain more lines, and the amount can change even when consumption remains stable.

Check the contract schedule for words such as:

• Included
• Fixed
• Pass-through
• Reconciliation
• Forecast
• Actual
• Subject to change

A contract described simply as “fixed” does not necessarily guarantee that every component is fixed.

Understanding a business gas bill

A gas invoice normally shows:

• Meter Point Reference Number
• Meter serial number
• Opening and closing readings
• Whether each reading is actual or estimated
• Meter units
• Calorific value
• Volume-correction factor
• Converted consumption in kWh
• Unit and standing-charge rates
• CCL and VAT

Gas meters record volume, but suppliers charge for energy. The recorded cubic metres or cubic feet must therefore be converted into kWh.

What is an MPRN?

The Meter Point Reference Number identifies a gas supply point. It is generally a number of up to 10 digits.

Like an MPAN, an MPRN belongs to the supply point rather than the physical meter. It should remain the same when you switch supplier or replace a meter.

Do not confuse it with:

• Your gas account number
• The meter serial number
• An electricity MPAN
• The property’s postcode

A commercial site with several gas supplies can have more than one MPRN.

How gas units are converted to kWh

For a metric gas meter, the standard calculation is:

kWh = cubic metres used × correction factor × calorific value ÷ 3.6

The correction factor commonly shown on bills is 1.02264. The calorific value reflects the energy contained in the gas and can vary by billing period and region.

For example:

1,000m³ × 1.02264 × 39.5 ÷ 3.6 = 11,220.63kWh

The supplier should print the conversion calculation or its component values on the invoice.

Older imperial meters record hundreds of cubic feet. Their calculation includes an additional conversion into cubic metres, commonly shown as a factor of 2.83. Follow the formula printed on the invoice rather than assuming the displayed meter units.

Worked business gas bill example

This example uses 1,000m³ of gas over 31 days.

The tariff is 5p/kWh, excluding CCL, with a 70p daily standing charge.

Invoice item	Calculation	Cost
Converted gas consumption	1,000m³ × 1.02264 × 39.5 ÷ 3.6	11,220.63kWh
Gas used	11,220.63 kWh × 5p	£561.03
Standing charge	31 days × 70p	£21.70
CCL	11,220.63 kWh × 0.801p	£89.88
Subtotal		£672.61
VAT at 20%		£134.52
Total invoice		£807.13

The tariff and calorific value are illustrative.

Climate Change Levy explained

The Climate Change Levy is an environmental tax on energy supplied to most businesses and public-sector organisations.

From 1 April 2026, the main CCL rates for electricity and natural gas are both:

0.801p per kWh

The rate is applied to eligible consumption, normally before VAT. As VAT is calculated on a total that includes CCL, VAT is effectively charged on the levy as well as the underlying energy.

Certain supplies may qualify for an exemption or reduction, including:

• Qualifying low-use supplies
• Energy used by charities for non-business activities
• Some domestic or mixed-use supplies
• Eligible energy-intensive facilities covered by a Climate Change Agreement
• Certain forms of energy used for specified processes or purposes

Businesses with a qualifying Climate Change Agreement receive a 92% discount from the main electricity rate and an 89% discount from the main gas rate.

Do not remove CCL from your own calculation without confirming eligibility. The supplier may require an exemption or relief certificate.

Current and future rates are published in the government’s Climate Change Levy rate tables.

Why is VAT charged at 20%?

Standard business energy use is generally subject to VAT at 20%.

A reduced rate of 5% can apply to qualifying supplies, including certain low-consumption, charitable, domestic and mixed-use situations.

HMRC’s de minimis thresholds are broadly:

Fuel	Low-consumption threshold
Electricity	No more than 33kWh per day or 1,000kWh per month
Piped gas	No more than 145kWh per day or 4,397kWh per month

Where at least 60% of a mixed supply qualifies for reduced-rate treatment, the whole supply may qualify for the 5% rate. Otherwise, the qualifying and non-qualifying portions may need to be apportioned.

Supplies receiving reduced-rate VAT treatment are generally excluded from CCL. Eligibility can depend on the nature of the organisation and how the energy is used, not simply the amount on one invoice.

Read HMRC’s VAT Notice 701/19 and our guide to VAT on business energy before submitting a declaration to your supplier.

Why has the supplier estimated my usage?

An estimated reading may be used when:

• The supplier cannot access the meter
• A smart or half-hourly meter has stopped communicating
• No manual reading was submitted
• Meter data failed validation
• The invoice was produced before data became available
• The account or meter has recently changed

Compare the estimated closing reading with the physical meter. If it is wrong:

1. Photograph the meter display and serial number.
2. Record the date and time.
3. Submit the reading through the supplier’s accepted channel.
4. Ask for the invoice to be cancelled and reissued.
5. Keep the original invoice and corrected version.
6. Check that the correction is not charged again later.

If the physical reading is below the billed reading, the supplier has probably overestimated consumption. If it is higher, an additional charge may follow when the account is reconciled.

Common business energy billing errors

• Wrong supply point: The MPAN or MPRN belongs to another unit, floor, tenant or building. This is particularly common on industrial estates and at subdivided premises.
• Wrong meter serial number: The supplier is billing an old meter or has associated readings with the wrong supply.
• Estimated readings: The supplier’s estimate does not reflect seasonal or operational changes.
• Incorrect multiplier: A current-transformer meter has been billed using the wrong multiplier or ratio.
• Duplicate billing periods: Two invoices charge for the same dates or the same meter consumption.
• Missing contract rate: The bill uses deemed, out-of-contract or incorrect renewal prices instead of the agreed tariff.
• Incorrect contract dates: The new tariff began later than expected, or the old rate continued after the contractual change date.
• Wrong number of standing-charge days: The supplier has charged too many days or duplicated the standing charge across an adjustment.
• Incorrect CCL or VAT: A valid exemption, reduced rate or Climate Change Agreement discount has not been applied.
• Missing payment or credit: A Direct Debit, credit note or agreed refund is absent from the account.
• Unexplained capacity charges: The billed capacity differs from the agreed maximum import capacity, or the site is repeatedly incurring excess charges.
• Previous occupier’s consumption: The supplier’s opening reading predates your occupation of the premises.
• Incorrect gas conversion: The bill uses the wrong meter units, correction data or meter exchange reading.

How to check a business energy bill

Use the following process every month.

Our business energy cost calculator guide explains how to estimate future invoices using consumption and tariff data.

What to send when disputing a bill

Provide evidence that enables the supplier to investigate the correct supply and invoice:

• Account and invoice numbers
• Supply address
• MPAN or MPRN
• Meter serial number
• Dated photographs of the meter
• Opening and closing readings
• Copy of the contract or renewal confirmation
• Previous invoices
• Bank evidence for missing payments
• Meter exchange documentation
• Half-hourly consumption data, where relevant
• Your own calculation of the disputed amount

State exactly which line is disputed and why. Asking the supplier simply to “check the bill” is less effective than identifying the reading, rate, period or tax treatment you believe is wrong.

Request that the issue is registered as a formal complaint and ask for a complaint reference.

Business energy back-billing rules

Ofgem’s back-billing protection generally prevents suppliers from charging a microbusiness for energy used more than 12 months earlier when the supplier failed to bill correctly.

Protection may not apply if the business acted unreasonably—for example, by obstructing meter access, ignoring reasonable requests for readings or preventing accurate billing.

The rule does not provide the same general protection to every larger business. Contract terms and the circumstances of the error become particularly important outside the microbusiness definition.

A business can qualify as a microbusiness through its staff and financial size or through its annual consumption. The consumption limits are:

• Electricity: no more than 100,000kWh annually
• Gas: no more than 293,000kWh annually

See Ofgem’s guidance on business energy back-bills.

Escalating an unresolved complaint

Give the supplier an opportunity to investigate through its formal complaints process.

Eligible microbusinesses and small businesses can refer an unresolved dispute to the Energy Ombudsman after eight weeks, or sooner if the supplier issues a deadlock or final-response letter.

Small-business eligibility includes organisations that meet the relevant staff and financial test, or consume no more than:

• 200,000kWh of electricity annually
• 500,000kWh of gas annually

The Ombudsman can examine disputes involving billing, contracts, metering, switching and customer service. Its service is free for eligible businesses. Check the Energy Ombudsman’s business eligibility guidance before submitting a case.

Business energy bill glossary

Term	Meaning
Actual reading	A verified meter reading rather than an estimate
Agreed capacity	Electrical capacity reserved for a site
CCL	Climate Change Levy
Consumption	Energy used, normally measured in kWh
Credit note	Document reducing or reversing an earlier invoice
Deemed rate	Rate applied without an agreed current contract
DUoS	Distribution Use of System
Estimated reading	Supplier-calculated reading used when actual data is unavailable
kVA	Apparent electrical power
kVArh	Reactive electrical energy
kW	Rate of active electricity demand
kWh	Unit of consumed energy
Maximum demand	Highest average demand during a settlement interval
Meter multiplier	Number used to convert recorded units into billable consumption
MPAN	Identifier for an electricity supply point
MPRN	Identifier for a gas supply point
MSN	Serial number identifying a physical meter
Pass-through charge	Cost charged at its prevailing rather than fixed rate
Power factor	Relationship between useful and apparent power
Standing charge	Daily fixed charge for maintaining the supply
TNUoS	Transmission Network Use of System
Unit rate	Price charged for each kWh
VAT	Value Added Tax

FAQ

Final bill-checking checklist

Before approving an invoice for payment, confirm:

• The correct premises and supply point are being billed.
• Meter serial numbers match the installed meters.
• The billing dates are complete and non-overlapping.
• Readings and multipliers produce the stated consumption.
• Every unit rate matches the contract.
• The number of standing-charge days is correct.
• Capacity and reactive-power figures are reasonable.
• CCL and VAT have been applied correctly.
• Payments and credits are present.
• Any adjustment can be traced to a supporting calculation.

Checking these fields routinely can identify errors before they become large account balances. It also produces cleaner consumption data, making it easier to compare business energy quotations when the contract approaches renewal.