Your Energy Supplier Went Insolvent in Frankfurt: Mainova Takes Over for Up to Three Months, and What to Do in That Window
If your electricity or gas supplier stops delivering because it is insolvent, the lights do not go out: the local basic supplier takes over by law, and in Frankfurt that is Mainova. The replacement supply lasts at most three months (§ 38 EnWG), at a price that is usually higher than other tariffs, and you can leave it for a new supplier at any time without notice. After the three months, household customers are moved to the basic supply tariff automatically. Read your meter on the day, tell the network operator, Mainova and your old supplier, and cancel the direct debit to the insolvent company.
The Law Keeps Your Supply On
When a supplier collapses, the business relationship ends, but your connection to the grid does not. Under § 38 EnWG, if a consumer draws energy and the draw cannot be assigned to a supply or a contract, the energy counts as delivered by the basic supplier, who has to supply the area. This is called Ersatzversorgung, replacement supply. The Bundesnetzagentur puts it simply: if an insolvent supplier no longer delivers, the local basic and replacement supplier takes over and is legally obliged to.
In Frankfurt that supplier is Mainova. A 2021 press release shows how it works in practice: when the discount gas company gas.de stopped delivering, Mainova took over more than 5,000 former customers as basic supplier in Frankfurt and the surrounding municipalities and informed them in writing. Mainova’s own pages for electricity and gas say that your last bill shows who your responsible basic supplier is.
What the Three Months Mean
| Phase | What applies | Your options |
|---|---|---|
| Day 1 until month 3 | Replacement supply by Mainova at its separate replacement prices (§ 38 EnWG) | Switch to a special contract with Mainova or to another supplier at any time, no notice period |
| After 3 months | Household customers move on to basic supply, "Mainova Strom Classic" or "Mainova Erdgas Classic" | Normal basic supply terms and a normal right to change tariff |
The relationship under § 38 ends once you are supplied under a contract you chose yourself, and at the latest three months after replacement supply begins. The Bundesnetzagentur warns that the replacement tariff is mostly more expensive than other tariffs. The basic supplier can change these prices on the 1st and the 15th of any month and must show the past six months of prices on its website, and the law caps the procurement cost it may build in. Treat the period as a bridge: use it to compare tariffs, as described in our guide to choosing an energy tariff in Frankfurt.
Your First Day Checklist
The Bundesnetzagentur lists these steps, and Mainova gives the same advice to its former gas.de customers:
- Read your meter and note the date. Report the figure to the network operator, to Mainova and to your former supplier. In the Frankfurt grid area, NRM Netzdienste Rhein-Main is the local metering point operator and has a page for submitting readings. Our page on meter reading submission shows the routes.
- Revoke the direct debit you gave to the insolvent supplier. Delete standing orders at your bank, and pay upcoming amounts only by one-off transfer.
- Cancel the old contract. Mainova’s press release says the contract with the insolvent company still exists even after Mainova delivers, so it is best to terminate it.
- Keep your documents: the last bill, the contract and any letter from the insolvency administrator.
- Watch for Mainova’s letter. Once it learns that you are supplied by it, the basic supplier has to inform you about the replacement supply, the prices and the conditions.
Money Owed in Both Directions
The Bundesnetzagentur describes how the money side works. The insolvency administrator is responsible for settling the energy supplied. A final bill should reach you within six weeks after the supply ends, but the agency tells customers to expect that this deadline may not be met. If it shows a balance in your favour, you cannot get an immediate refund: you can only register the credit as a claim in the insolvency table. If the final bill shows you owe money and the claim is correct, you pay it to the account named by the administrator, not to the old bank details.
Check the final bill for the advance payments you made, the meter readings and the tariffs. If you already asked the supplier to correct a bill, repeat your objection to the administrator.
If Your Supplier Is Insolvent but Still Delivers
An insolvency alone gives you no special right to cancel. The Bundesnetzagentur says that you can end the contract only under the contractual notice period, which is usually in the terms and mentioned on your last bill. As long as the supplier keeps delivering, you must keep paying the advances. Check with the administrator which account to pay to, since the bank details can change.
This is also the situation in which a switch makes sense once your contract allows it. If you want a planning tool, see our page on adjusting your monthly Abschlag.
A Short Plan
- Do not panic: the supply continues, and Mainova is the Frankfurt basic supplier.
- Read the meter and send the figure to NRM, Mainova and the old supplier.
- Stop the direct debit and cancel the old contract.
- Compare tariffs within the three months, and change whenever you find a better one.
- Report any credit as a claim and check the final bill.
Compliance Note
This guide summarises § 38 EnWG, the pages of the Bundesnetzagentur and the pages of Mainova and NRM Netzdienste Rhein-Main as read in October 2026. Prices, tariffs and procedures change, and your own contract decides your notice period. This is not legal advice. Confirm the details with Mainova or the insolvency administrator.
FAQ & Common Pitfalls
Will my power or gas be cut off if my supplier goes insolvent?
No. According to the Bundesnetzagentur, when an insolvent supplier stops delivering, the local basic and replacement supplier takes over your supply and is obliged by law to do so. In Frankfurt, Mainova states that it steps in as the local basic supplier in its area. You do not need to sign anything for the supply to continue, because under § 38 EnWG the energy you draw counts as delivered by the basic supplier.
How do I know who the basic supplier at my address is?
Mainova says your last bill shows who the responsible basic supplier is for that consumption point. The Bundesnetzagentur adds that the local network operator can tell you, and it has to publish the name on its website. In the Frankfurt grid area, NRM Netzdienste Rhein-Main is the local metering point operator and reads the meters. A 2021 Mainova press release describes it as basic supplier in Frankfurt and surrounding municipalities, so addresses just outside the city may differ.
How long does the replacement supply last, and what happens after?
At most three months from the start, under § 38 Abs. 4 EnWG. Mainova says household customers are then supplied seamlessly in the basic supply tariff, called Mainova Strom Classic for electricity and Mainova Erdgas Classic for gas. The Bundesnetzagentur notes that during these three months the basic supplier is not obliged to offer ordinary basic supply, so the two are separate phases.
Is the replacement supply more expensive?
Usually yes. The Bundesnetzagentur says you will be put into the replacement tariff, which is mostly more expensive than other tariffs. The law lets the basic supplier publish separate general prices for it and adjust them on the 1st and the 15th of a month. It must show the procurement costs separately and may not calculate them higher than short-term exchange purchase would cost. The supplier must keep the prices of at least the last six months on its website. That is the reason to compare tariffs soon.
Can I switch to a new supplier during the three months?
Yes, at any time and without a notice period. The Bundesnetzagentur says that in replacement supply you can look for a new supplier whenever you like, and Mainova says the same: during the maximum of three months you can conclude a special contract at any time, without waiting for a notice period. Our page on choosing an energy tariff in Frankfurt explains what to compare.
What should I do in the first days?
The Bundesnetzagentur advises to read the meter as soon as possible and report the reading to the network operator, the local basic or replacement supplier and the former supplier. Revoke the direct debit mandate you gave to the insolvent supplier, delete standing orders at your bank and make any upcoming payment as a one-off transfer only. Mainova also advises to terminate the old contract with the insolvent company, because the paper contract still exists.
What about my credit or bonus from the old supplier?
If you had a credit balance or a bonus, it is not refunded during the insolvency proceedings. According to the Bundesnetzagentur, you can only register it as a claim in the insolvency table. If the final bill shows you owe money and the claim is correct, you pay it to the account named by the insolvency administrator. Check the final bill carefully: figures for advance payments, meter readings and tariffs can be wrong.
My supplier is insolvent but still delivers. Can I leave right away?
Not because of the insolvency alone. The Bundesnetzagentur says that in this case you have no special termination right and can end the contract only within the contractual notice period, which usually appears in the terms and on your last bill. Keep paying your monthly advances to the account the insolvency administrator gives you, as long as the supplier keeps delivering.