Setting Up Utilities in Idaho Falls: Idaho Falls Power vs Rocky Mountain Power, Intermountain Gas, Water & Trash

Short answer: In Idaho Falls, your electric company depends on whether the home is inside Idaho Falls city limits. Inside the city, Idaho Falls Power and the City of Idaho Falls handle electric, water, sewer and trash on one bill. Ammon and most nearby towns use Rocky Mountain Power for electric, and Intermountain Gas is the natural gas company across the area. Water, sewer and trash come from the city (or a district) that serves your address.

The fastest way to get it right is to confirm the city limits for the exact address first. Then call or apply 1 to 2 weeks before you close or move in. Intermountain Gas asks for at least 2 business days' notice. I checked every phone number, form and fee below on the official provider and city websites on October 13, 2026.

I'm Jacob Marcovitz, a REALTOR® with Keller Williams Realty East Idaho. I help Idaho National Laboratory (INL) relocators and out-of-state buyers move to Idaho Falls and Ammon, and "who do I call for power?" is one of the first questions I get after an offer is accepted. If you're still deciding between the two cities, start with Idaho Falls vs. Ammon.

Electric

• Inside Idaho Falls city limits: Idaho Falls Power (city-owned). Start it through City Utilities: 208-612-8280
• City of Ammon: Rocky Mountain Power: 1-888-221-7070, or start service online

Natural gas

• Inside Idaho Falls city limits: Intermountain Gas: 800-548-3679
• City of Ammon: Intermountain Gas: 800-548-3679

Water and sewer

• Inside Idaho Falls city limits: City of Idaho Falls, on the same city utility account
• City of Ammon: City of Ammon for most addresses (Falls Water serves some developments to the north): 208-612-4000

Trash

• Inside Idaho Falls city limits: City of Idaho Falls Sanitation, on the same account
• City of Ammon: City of Ammon Sanitation, on your city utility account

City fiber internet

• Inside Idaho Falls city limits: Idaho Falls Fiber: 208-612-8725 (sign-up required)
• City of Ammon: Ammon Fiber (city open-access network); check the map for your street

Who provides electricity in Idaho Falls vs. Ammon?

Idaho Falls Power is a municipal utility, and its own outage page says it "only serves customers within the city limits of Idaho Falls." The same page lists Ammon, Blackfoot, Iona, Rexburg, Rigby, Ririe, Shelley and Ucon as places outside its territory. It points those customers to their own provider: Rocky Mountain Power (877) 508-5088, Idaho Power (800) 488-6151 or Fall River Rural Electric (800) 632-5726.

The Idaho PUC's "Utilities by City" list, still linked from its Maps & Lists page (the posted edition is dated 2012), shows the town-level picture:

Idaho Falls

• Electric (Idaho PUC list): Idaho Falls Power (listed as "Idaho Falls Electric")
• Natural gas (Idaho PUC list): Intermountain Gas

Ammon

• Electric (Idaho PUC list): Rocky Mountain Power
• Natural gas (Idaho PUC list): Intermountain Gas

Iona, Ucon, Rigby, Ririe, Shelley, Firth

• Electric (Idaho PUC list): Rocky Mountain Power
• Natural gas (Idaho PUC list): Intermountain Gas

Blackfoot

• Electric (Idaho PUC list): Idaho Power
• Natural gas (Idaho PUC list): Intermountain Gas

Rexburg, Sugar City, St. Anthony

• Electric (Idaho PUC list): Rocky Mountain Power / Fall River Co-op
• Natural gas (Idaho PUC list): Intermountain Gas

That list is by town, not by street, so use it as a starting point only. Here's how I confirm the provider for a specific house:

• Don't go by the mailing address. A home can have an "Idaho Falls" mailing address and still sit outside city limits. What matters is whether the parcel is inside the city.
• Ask for the seller's providers. I ask the listing agent which electric, gas, water and trash companies the seller uses. It's the quickest real-world answer.
• Check Ammon's map. The City of Ammon has an "Am I in Ammon?" GIS map. The city also notes that if a home gets City of Ammon garbage service, it's inside Ammon city limits.
• Call the city. Idaho Falls City Utilities is at 208-612-8280, and Ammon City Hall is at 208-612-4000. Either office can tell you whether they serve an address.

How do I start Idaho Falls Power, water, sewer and trash?

Inside city limits, this is a one-stop shop. Idaho Falls Power is a division of the City of Idaho Falls, and the city puts electric, water, sewer and garbage on one utility bill. You start, stop or move all of them through City Utilities at City Hall, 308 Constitution Way.

1. Apply. Use the online Residential Utility Application on the city's Utilities page, or go to the City Utilities office in person. Idaho Falls Power's FAQ also says the city can email you the paperwork if you ask at utilities@idahofallsidaho.gov.
2. Have these ready: a photo ID, your Social Security number, proof of residence (the city lists a rental or lease agreement; buyers should have their closing paperwork handy) and your signature.
3. Register for the portal. The city's welcome packet says you'll need your new account number to set up the customer self-service portal. For a residential account, you'll also need the primary account holder's last name and the last 4 digits of their Social Security number.
4. Choose how to pay. The city charges a $4.50 processing fee on card and one-time payments. Paperless billing saves $1 a month. Budget Billing (level pay) requires a year at the address.

Phone numbers worth saving: City Utilities office 208-612-8280, Idaho Falls Power and outages 208-612-8430, after-hours power (844) 746-3618, Water 208-612-8471, Wastewater 208-612-8108 and Sanitation 208-612-8491.

For trash, the city's welcome packet lists sanitation as part of city utilities, and city crews collect it. Since January 16, 2024, the city's recycling drop sites take glass only. If you want curbside recycling, the city's page points residents to Western Recycling and lists its residential fee at $14.00 a month, collected every two weeks. For what a typical bill looks like, see my Idaho Falls cost of living guide.

How do I start Rocky Mountain Power in Ammon and nearby towns?

If the home is in Ammon, or in one of the towns Idaho Falls Power sends to Rocky Mountain Power, you'll open an account with Rocky Mountain Power:

• Online: use "Start, stop or move" on rockymountainpower.net (choose Idaho).
• By phone: customer service is 1-888-221-7070.
• Outages and downed lines: 1-877-508-5088, or text OUT to 759677.

On deposits, Rocky Mountain Power's Idaho consumer information sheet says current customers with a good payment record, and new customers with good credit at their previous utility, won't need a security deposit. Other customers may be asked for one.

How do I set up natural gas with Intermountain Gas?

Intermountain Gas serves both Idaho Falls and Ammon. Here's what its website says today:

• New customers call. Call customer service at 800-548-3679 to start new service. Existing customers can also start, stop or transfer service online. Phone hours are 7:30 a.m. to 6:30 p.m., Monday through Friday.
• Give at least 2 business days. The online forms aren't for service needed within the next 2 business days, so call if you're closer than that. New connections are completed Monday through Friday, excluding holidays.
• Initiation fee. It's $14 if the gas is turned on during business hours (8 a.m. to 5 p.m., Monday through Friday) and $40 if you ask for an after-hours turn-on. The fee shows up on your first bill.
• Access. If the gas is already on, they only need access to the meter. If it's been shut off, an adult needs to be home when the technician comes.
• Deposit. You may need one if you haven't had Intermountain Gas service for 12 straight months in the last four years and don't pass a credit screen. A few other situations can trigger one too, such as unpaid prior service.

Who handles water, sewer and trash in Ammon and other towns?

In Ammon, the city provides water, sewer, garbage, fiber and pressurized irrigation, though the city notes these "vary by address." Most Ammon properties are on city water, but Falls Water serves several developments to the north. Wastewater is treated through two sewer districts, the Eastern Idaho Regional Sewer District and the Iona Bonneville Sewer District. Here's Ammon's posted start-up process:

1. Complete the Utility Service Application from the city's Utilities page.
2. Upload proof of closing or your lease.
3. Pay the deposit for a new account: $60 for sanitation only or $150 for water. You can pay by phone at 208-612-4000 with Visa, Mastercard or Discover (no American Express).

Ammon's guide also says utilities "are not shut off between residents" and that billing is based on the closing or lease date. Every single-family home of four units or fewer in Ammon is required to have city garbage service. You'll get your pickup day when you sign up. The Ammon utilities office is at 2135 South Ammon Road, and you can email utilities@cityofammon.us.

In Iona, Ucon, Rigby, Shelley and other nearby towns, water, sewer and trash depend on the city and the address. Rural homes may have a private well and septic instead. Call that town's city hall, and ask the listing agent what the seller uses. If you're comparing those towns, see Rigby, Iona, Ucon or Shelley: which satellite town fits?

What about internet in Idaho Falls and Ammon?

Both cities run their own open-access fiber networks. You sign up for the network and then pick an internet provider on it:

• Idaho Falls Fiber is owned by Idaho Falls Power. The city's welcome packet says fiber is now available for all city customers, with sign-up required. It advertises speeds up to one gigabit, download and upload. Call 208-612-8725 or see idahofallsfiber.com.
• Ammon Fiber is the City of Ammon's open-access fiber utility, and its residents can choose from multiple providers. Because the network is built out neighborhood by neighborhood, check the map at ammonfiber.com for your street.

Cable, DSL and wireless options vary by street. I don't list them here because coverage changes, so check providers by the exact address before you choose a home office setup.

When should I set up utilities before closing or move-in?

Here's the timeline I give my buyers:

• Once you're under contract: confirm city limits and the providers for the address.
• About 1 to 2 weeks before closing: apply with the city (Idaho Falls or Ammon), open your electric account if you're on Rocky Mountain Power, and schedule gas. Ask for service to start on your closing or possession date.
• At least 2 business days before you need gas: this is the minimum Intermountain Gas asks for. In winter, don't cut it close.
• The week you move in: register for online portals, set up autopay and sign up for fiber.

Sellers should stop service as of the closing date too. In Ammon, that's the city's Termination of Service request. If you're relocating for INL and will be in temporary housing first, read Don't Buy in Week One: Temporary Housing & Your First 90 Days. And because utilities are part of the monthly cost of owning, my property taxes and HOAs guide covers the rest of the budget.

Who sets up utilities on a new-construction home?

On a new build, the builder and its contractors usually handle getting service to the house. You take over the accounts at closing. Here's what the utilities say about that first connection:

• Idaho Falls Power: power to a new building depends on the building-permit inspections and on the service line conduit being installed and inspected to its service policy.
• Rocky Mountain Power: new homes go through its line-extension process, which includes a New Construction Hotline (1-800-469-3981), a possible site meeting with an estimator, and electrical and trench inspections before construction is scheduled.
• Intermountain Gas: before a meter is set, it asks whether the service line is in, whether the pressure test has been completed and inspected, and whether the house piping is tied to the meter bar. It says new subdivision homes "may have little or no cost," and that lead times run 2 to 6 weeks for a service line and 4 to 10 weeks for a main line extension. Those lead times get longer as cold weather approaches.

My advice: about two weeks before closing, ask the builder's closing coordinator which accounts are in the builder's name and what date they'll come out of it. Then start yours on that date so nothing gets shut off. Shopping new builds this fall? See Year-End New Construction in Idaho Falls and the Eastern Idaho new construction map.

More guides for relocating to Idaho Falls

• How to buy a home in Idaho Falls as an out-of-state relocator: the step-by-step guide to buying from a distance.
• INL relocation guide: what to know before you move for the lab.
• Temporary housing and your first 90 days: renting first, then buying.
• Idaho Falls vs. Ammon: schools, commute and the feel of each city.
• Cost of living in Idaho Falls: what utilities, taxes and housing cost.
• What winter is really like in Idaho Falls: useful if you'll be moving in the cold months.

Provider phone numbers, forms, fees and deposits on this page come from Idaho Falls Power, the City of Idaho Falls, Rocky Mountain Power, Intermountain Gas, the City of Ammon and the Idaho PUC, as of October 13, 2026. They change, so confirm with the provider before you schedule service. Rates aren't listed here on purpose.

Want me to confirm the providers for a home you're looking at, or help line up your move-in dates? Call or text me at 208-821-6217, or reach me through my contact page. — Jacob Marcovitz, REALTOR®, Keller Williams Realty East Idaho