Check who the notice is actually addressed to
If it says "occupant," "resident," or "current resident" instead of your name, that's your first clue the account belongs to your landlord. Call the utility using the number printed on the notice, tell them the property is tenant-occupied, and ask directly whose name is on the account. Minnesota's tenant fact sheet gives this exact advice: "Contact the utility company any time you get a bill that is in the landlord's name. Tell them that it is a tenant occupied property," because a utility that thinks the landlord still lives there may never mail you a notice at all (LawHelp Minnesota). If you're not sure and there's no notice yet, your lease should say who was supposed to set up the utilities in the first place. A tenant fact sheet from Ohio's utility consumer advocate puts it simply: "Renters should ask the landlord who is responsible for paying the utilities before signing a lease agreement" (Office of the Ohio Consumers' Counsel).
Call the utility before the date on the notice
Some states give you the right to put the account in your own name, without paying off what the landlord owes. In Illinois, "any tenant can ask the utility company to put the bill in the tenant's name" once the landlord has stopped paying, and if you have decent credit, or pay a deposit and agree to pay future bills, the company can't disconnect you and has to restore service if it already did (Illinois Legal Aid Online). California's investor-owned utilities have to make "every good faith effort" to tell occupants in writing, separately from the landlord, that they can become customers "without being required to pay any amount which may be due on the delinquent account" (Cal. Pub. Util. Code § 777). Maryland's law works the same way. A tenant "may apply for a new utility service account in the tenant's name" and "may not incur liability for charges due on the landlord's account," and the provider can't refuse or condition that on the landlord's unpaid balance (Md. Code, Pub. Util. § 7-309). Ask what proof of tenancy the utility wants. For a detached single-family home in California, the utility may ask you to verify that the delinquent customer of record was the landlord, manager or agent, and a lease, rent receipts or a government document showing you rent the place counts (Cal. Pub. Util. Code § 777(f)).
This is a real pattern, not a national rule. Every one of those protections comes from that state's own code, and plenty of states haven't been checked yet for this guide. If your state page on this site doesn't cover it, call your utility and ask what it does when a landlord's account goes unpaid in an occupied unit.
Advance notice to everyone in the building, not just the landlord
Several states require the utility to warn occupants separately before cutting service over a landlord's unpaid bill, on top of whatever notice goes to the landlord. Illinois requires this for buildings with three or more units: the utility "must tell the tenants at least 10 days before the shut-off," and the notice has to state the shutoff date, the tenants' right to pay and deduct from rent, and the name of a local free legal services agency (Illinois Legal Aid Online). California requires its investor-owned utilities to give at least 10 days' notice for an individually metered unit in the landlord's name, and at least 15 days, posted on every unit's door, for a master-metered building. A detached single-family home is the exception, and there the notice can be as short as seven days (Cal. Pub. Util. Code §§ 777, 777.1). Maryland requires 14 days when the bill goes to an address other than the property, and a specific warning on the envelope: "IMPORTANT NOTICE TO ALL OCCUPANTS: UTILITY TERMINATION PENDING" (Md. Code, Pub. Util. § 7-309). In Ohio, regulated utilities give the landlord 14 days' notice, and if the landlord doesn't act, a further 10 days' notice to each tenant on master-metered service (Office of the Ohio Consumers' Counsel). These numbers aren't interchangeable. Outside these four states, check your state page instead of assuming a notice period.
Getting your money back through your rent
If you end up paying the landlord's overdue bill yourself to keep the lights on, several states let you take that payment straight off your rent instead of suing to get it back. In Texas, if your lease made the landlord responsible for furnishing and paying for the water, gas or electricity, and the utility cuts off service or sends written notice that it will, you may "deduct from the tenant's rent, without necessity of judicial action, the amounts paid to the utility company to reconnect or avert a cutoff," as long as you give the landlord a copy of the utility receipt (Tex. Prop. Code § 92.301). Illinois allows the same thing: "you can withhold any payments you make from your rent," and it's illegal for the landlord to raise your rent to claw that money back (Illinois Legal Aid Online). Minnesota tells you to warn the landlord 48 hours before you pay, in writing or verbally, and to follow a verbal warning with written notice within 24 hours. You can give less than 48 hours if service is going off sooner than that. Then send the landlord a copy of the receipt and take the amount off your next rent payment (LawHelp Minnesota). In California, if you become the customer and your rent includes utility charges that aren't listed separately, you can deduct the reasonable charges you paid the utility from your next rent payment (Cal. Pub. Util. Code § 777(e)).
Texas and Minnesota both turn on a receipt from the utility, and a paper trail helps you anywhere. Keep every receipt from the utility and send the landlord a copy the same day, whatever your state's rule turns out to be.
If the building runs on one meter for everyone
Master-metered buildings are different, and it's worth knowing why before you call anyone. There's no separate meter measuring just your unit. In Ohio, for instance, "master meter utility service is required to be in the landlord's name," full stop, and utility bill assistance programs "are not typically available to master metered buildings since customers are not individually billed" (Office of the Ohio Consumers' Counsel). That's one reason this situation is under-served. The usual fixes assume an account with your name on it.
Some states have built a way around this. California grants the same right to become a customer even in a master-metered building, through one or more occupants or a representative acting for them, with 15 days' posted notice on every door (Cal. Pub. Util. Code § 777.1). New Jersey takes a collective approach, but only once three things have happened. The utility has given tenants written notice that it plans to discontinue service, the tenants have said they want to keep it, and the utility has decided it isn't feasible to bill each tenant individually (N.J. Rev. Stat. § 2A:18-61.60). Then a tenants' organization can accept the billing, and its members can deduct their share of the current bill from rent, plus a contribution to the landlord's arrears capped at 15 percent of what their rent would have been (N.J. Rev. Stat. § 2A:18-61.61). Ohio instead points tenants toward a court escrow account, where payments go to the local court or court clerk instead of the landlord and can be used to pay the utility bill to prevent disconnection (Office of the Ohio Consumers' Counsel). Three states, three mechanisms. In a master-metered building, call your state's public utility commission and ask what tenants there can actually do, because putting the account in your own name may not be an option.
Where to get help
A legal aid attorney can tell you what your specific lease and your specific state actually allow, which this guide can't do for you. LawHelp.org helps you find free legal help from nonprofit legal aid providers in your state. It's maintained by Pro Bono Net with legal aid and court-based programs around the country (LawHelp.org). Your state's public utility commission can tell you the notice period and rights that apply to your utility. Some run a consumer affairs office that takes complaints. Minnesota's says it handles "complaints on energy and telecommunications utility services, service quality, billing problems, and service disconnections and reconnections," and its page lists the current number to call (Minnesota Public Utilities Commission). Check whether yours does the same. If your building has other tenants in the same situation, a tenant union or tenant organizing group can help you act together, which matters most in master-metered buildings where an individual fix may not exist at all.
What this guide can't tell you
This is not legal advice, and it can't be. Whether your landlord's failure to pay breaches your specific lease, whether you can withhold rent safely in your specific city, and what a judge would actually do with your specific facts are all questions for a lawyer who has read your lease and your state's law, not a guide written for readers everywhere. If money is tight, legal aid intake is usually free, and this is exactly the kind of question they exist to answer.