Explainer
How to change your electricity or gas supplier step by step
Changing supplier is free by law, but the contract with the old supplier may have its own rules. This guide is for anyone who wants to move to another supplier: the steps, the deadlines and when a contractual penalty can be avoided.
Prepared by the Banbosh Studio editors with AI from the comparison's data; first published 15 October 2026. Facts checked on 15 October 2026 against the 9 sources listed at the end. Text last updated 15 October 2026.
The short answer
First find out from the bill what contract you have and when it can end without a penalty. Then sign with the new supplier, arrange the notice to the old one (yourself, or by power of attorney) and report the meter reading after the switch.
- The procedure applies to households as consumers; business contracts have some deadlines different.
- Whether the change pays off depends on the new offer's price and on any penalty; the result cannot be guaranteed.
When a contract can end without a penalty
- Situation: Indefinite-term contract
- How to end it: NoticeDeadline: Usually 3 months from the first day of the month after delivery; the contract may set a shorter one
- Situation: Fixed-term contract with renewal
- How to end it: Notice before the renewalDeadline: At any time up to the 20th day before the end of the agreed period
- Situation: The supplier raised the price or changed terms
- How to end it: Notice under the Energy ActDeadline: At the latest on the 10th day before the announced date of change
- Situation: Contract concluded at a distance or away from the supplier's premises
- How to end it: Withdrawal, or notice when changing supplierDeadline: Withdrawal within 14 days of the contract; notice up to the 15th day after supply starts
- Situation: Moving, loss of ownership or right of use
- How to end it: NoticeDeadline: 15 days' notice from the first day of the month after delivery
- Situation: An intermediary signed the contract for you
- How to end it: NoticeDeadline: Up to the 15th day after supply starts
- Situation: Dynamic (spot) price
- How to end it: NoticeDeadline: At any time, 1 month's notice
Decision flow: how to end the old contract
Do you have an indefinite-term contract?
Yes → Terminate it; the notice period is usually 3 months from the first day of the next month, the contract may set a shorter one.
Are you moving, or did you sign at a distance, away from the supplier's premises or through an intermediary?
Yes → You have a legal right to end the contract without a penalty: see the table and deadlines above.
Is it a fixed-term contract nearing its end?
Yes → Terminate it by the 20th day before the end of the agreed period so that it does not renew.
No → Work out the penalty and compare it with the saving; the change may not pay off.
Step 1: find out what your contract says
From the bill and the contract write down the supplier, the supply point number (EAN), the distribution rate, the breaker and the yearly consumption. Also important are the duration of the contract (fixed or indefinite), the notice period and the amount of the penalty. The terms and conditions must be part of the contract and, according to ERÚ, are also on the supplier's website.
How to find these data on the bill, the guide on reading a bill explains.
Between the cheapest and the dearest offer lie up to CZK 9,630 a year.
Orange: the cheapest yearly total, blue: the dearest, per distribution area (up to 51 offers in an area). Rate D02d, 2.5 MWh a year, breaker 3x25 A, VAT included; price lists checked on 10/8/2026 or later, regulated part valid from 1/1/2026. An estimate, not a bill.
For a household on rate D02d with 2.5 MWh a year the regulated part costs CZK 8,508 to CZK 11,343 a year; it depends only on the distributor.
Orange: the regulated part (ERÚ price decisions valid from 1/1/2026), blue: the lowest supplier part of the offers in our comparison. A year with VAT, breaker 3x25 A, supplier price lists checked on 10/8/2026 or later. An estimate, not a bill.
Step 2: compare offers and count the penalty
ERÚ recommends comparing specific suppliers and not looking only at the lowest price: customer satisfaction, the amount of the penalty, the option of an indefinite-term contract and clear terms and conditions matter. You can compare offers in ERÚ's comparison tool. The comparison on Fordeal is still being prepared and does not replace checking the price list.
The law guarantees that changing supplier is free. That does not mean a contractual penalty for ending a fixed-term contract early cannot apply. ERÚ states that such a contract can be ended free of charge only in cases set by law, for example a price rise, moving, or a contract concluded at a distance.
Penalties are fixed or depend on the months left. What the change saves is an estimate, not a guarantee.
Step 3: sign with the new supplier
With the new supplier you conclude a contract for the combined supply services: the supplier usually also arranges the contract with the distributor. Before signing, have the contract, the valid price list and the terms and conditions shown to you. If you want supply to start on a certain date, have the date written into the contract.
You can give the new supplier a power of attorney to terminate the old contract and handle the change, or do it all yourself. Many suppliers have a link on their website to start the change, and often it can be done by e-mail.
Step 4: terminate the old contract
Give notice in writing and keep proof of delivery; ERÚ offers templates for each reason. Deadlines usually start on the first day of the month after the notice is delivered, so the delivery date matters. If you terminate under the law in one of the special cases, cite the provision of the Energy Act, for example section 11b, 11c, 11e or 11ca.
Remember that for a fixed-term contract the notice must expire before the renewal, otherwise the contract renews. The supplier must announce a renewal at least 30 days ahead.
Step 5: moving to the new supplier
According to ERÚ a standard change of supplier takes at least 10 working days. The whole process takes one to three months depending on notice periods for indefinite-term contracts, and longer for fixed-term ones. Supply cannot start overnight.
Supply is not interrupted. You cannot change the distributor, as it is set by territory, and the connection contract stays the same; only the supplier changes. Regulated distribution prices are the same whichever supplier you have.
Step 6: after the change
ERÚ recommends reporting a self-reading to the distributor for the day of change within five working days. The old supplier sends you the final bill within 15 days of receiving the consumption data from the distributor; in practice that is about one to two months. Then redirect your payments to the new supplier's account.
On the first bill from the new supplier, check that it matches the contract terms and the price list.
What stays the same and what changes
- Stays: the distributor and the connection contract, regulated distribution prices, the supply point (EAN).
- Changes: the supplier, the commercial part of the price (price for consumption, fixed fee), the terms and conditions, the account for payments and the conditions for ending the contract.
Who it is for
- You have an indefinite-term contract and want a new supplier.
- A fixed-term contract is nearing its end or its renewal.
- You are moving, or signed the contract at a distance or away from the supplier's premises.
Watch out for
- A penalty for ending a fixed-term contract early: it can be ended free of charge only in the special cases set by law.
- The price list and the terms and conditions must be part of the contract; read them before signing.
- After the change, pay the new supplier's account.
Frequently asked questions
- Does changing supplier cost money?
- Under the Energy Act a change of supplier is free. A contractual penalty for ending a fixed-term contract early may still apply.
- How long does a change take?
- Normally at least 10 working days. According to ERÚ the whole process takes one to three months for indefinite-term contracts, longer for fixed-term ones.
- Will I be left without electricity or gas?
- No. The distributor and the connection contract stay the same; only the supplier changes.
- When do I avoid a contractual penalty?
- For example with an indefinite-term contract, with notice by the 20th day before a renewal, after a price rise by the supplier, when moving, or with a contract concluded at a distance or away from the supplier's premises within the set deadlines.
- What should I do after the change?
- Report a self-reading to the distributor within five working days, wait for the final bill from the old supplier and redirect payments to the new one.