Irish electricity bills pack a surprising amount of information into a small space — and much of it is unexplained. If you have ever looked at a bill and wondered why the figure is what it is, or whether you are being charged correctly, this guide walks through every section from top to bottom.
The Header Section
At the top of your bill you will find:
- Account number — your unique reference with this supplier
- MPRN (Meter Point Reference Number) — the 11-digit number that identifies your electricity connection at the national network level. This number stays the same regardless of which supplier you are with. You will need it when switching.
- Billing period — the dates covered by this bill, usually 60 or 90 days
- Bill date and payment due date
Estimated vs Actual Readings
One of the most common causes of an unexpectedly high or low bill is the difference between an estimated reading and an actual reading.
Your electricity meter is read by ESB Networks approximately every six months. In between, most suppliers issue bills based on an estimated reading — a calculation based on your historical usage. If you have changed your usage habits significantly (working from home, buying an EV, installing a heat pump), estimated bills can be well off.
To avoid this, submit your own meter reading via your supplier's app or website at the start of each billing period. This triggers an actual-read bill and removes the risk of over- or under-paying. If you have a smart meter, readings are transmitted automatically — no manual submission needed.
The Usage Section
This section shows:
- Opening reading — meter reading at the start of the period
- Closing reading — meter reading at the end of the period
- Units consumed (kWh) — the difference between the two readings
If you are on a day/night (Smart/Nite) tariff, you will see two sets of readings: one for daytime units and one for overnight units, each at a different rate.
Unit Rate (c/kWh)
The unit rate is the price you pay per kilowatt-hour of electricity consumed. It is the single biggest variable in your bill and the main figure to compare when switching suppliers.
Example: A unit rate of 30c/kWh and 1,000 kWh consumed = €300 in usage charges.
If you are on a discounted new customer tariff, your unit rate is reduced by the discount percentage for the promotional period. After the discount expires, the rate reverts to the supplier's standard unit rate — which is why checking when your discount ends matters.
Standing Charge (c/day)
The standing charge is a fixed daily fee charged regardless of how much electricity you use. It covers the cost of your connection to the national grid. In Ireland, standing charges typically range from 50c to over €1 per day — equating to €180 to €380 per year at the extremes.
Example: A standing charge of 65c/day over a 90-day billing period = €58.50.
Standing charges receive less attention than unit rates but can significantly affect the total cost, particularly for low-usage households. A plan with a very low unit rate but a high standing charge can work out more expensive than it appears.
The PSO Levy
The Public Service Obligation (PSO) levy is a government charge that appears on every Irish electricity bill. It funds:
- Supports for renewable energy generation (wind, solar)
- Peat-fired generation at ESB's Midlands stations (being phased out)
- Energy security measures
The PSO levy is set annually by the Commission for Regulation of Utilities (CRU) and is the same for every supplier — it is not a supplier margin, and you cannot avoid it by switching. In some years the levy has been negative (a credit on bills) when renewable energy revenues were high enough to offset the cost.
VAT
Electricity in Ireland is subject to VAT at 13.5% (the reduced rate, not the standard 23%). All prices quoted by suppliers are typically inclusive of VAT. Your bill will show a VAT breakdown confirming the amount charged.
Carbon Tax (Gas Bills Only)
If you have a gas bill, it will include a carbon tax component — a per-kWh charge on natural gas consumption, set by the government and increased incrementally each year under the Climate Action Plan. Like the PSO levy, carbon tax applies equally across all suppliers and is passed through to the consumer.
Verifying the Maths
To check your own bill:
- Usage charge = unit rate (including VAT) × kWh consumed
- Standing charge total = daily rate × number of days in billing period
- Add PSO levy (shown as a fixed line item or included in the unit rate depending on supplier)
- Total before credit = usage charge + standing charge + PSO
If the figure on your bill does not match within a few cents, it is likely due to an estimated reading or a mid-period rate change. Contact your supplier with the specific discrepancy.
What to Do If Your Bill Seems Wrong
- Submit a meter reading and request a revised bill
- Check whether your discount has expired — the most common cause of a sudden bill increase
- Request a billing breakdown from your supplier — they are obliged to provide one under CRU rules
And if your unit rate now looks expensive compared to the market, that is a prompt to compare tariffs and switch.
Understanding your bill puts you in a much stronger position to know whether you are on a good rate — or whether switching would put a few hundred euros back in your pocket this year.