APS rate case: what changes for Arizona solar homes

Short answer: APS has asked the Arizona Corporation Commission for a 13.99% revenue increase, about $20 a month for a typical home using 1,000 kWh, and a final vote is expected toward the end of 2026. The case also proposes raising the Grid Access Charge for rooftop solar homes from about $2.50 a month to roughly $6, even though an appeals court threw out the current version in June. Separately, the export credit for new APS solar customers dropped 10% on September 1.

That's three moving parts on one bill. If you own, buy or sell a home with solar in APS territory, each one touches the numbers.

What is APS asking for?

APS filed its rate case on June 13, 2025, under docket E-01345A-25-0105. The request is a 13.99% net increase in what the utility collects. APS puts the typical residential bump at about $20 a month for a home using 1,000 kWh.

The Attorney General's office describes the request as a $608.7 million increase.

APS also wants a formula rate. That's a yearly adjustment based on the prior year's costs, instead of a full rate case every few years. APS says it would make changes more gradual, up or down.

When will the commission decide?

The evidentiary hearing started May 18, 2026. Next, an administrative law judge writes a Recommended Opinion and Order. APS and the other parties can file objections. Then the five commissioners vote.

APS and the commission both expect the case to wrap up by the end of 2026. Base rates don't change until that vote happens.

So no, your October bill isn't the new rate. It just feels that way after a Phoenix summer.

One small bit of good news in the meantime: on October 8 the commission approved a one-time credit for APS customers. The monthly environmental charge is waived on November 2026 bills, and the commission says the average home will see about $15 back.

Why is the Attorney General asking for an investigation?

On October 9, Attorney General Kris Mayes asked the commission to look into whether a billing mechanism called the Power Supply Adjuster shifted costs from a handful of large energy users, such as data centers, onto everyone else.

The request follows an analysis filed in the commission's dockets on October 2. It estimates $587 million in costs from 2023 through 2025 may have landed on other customers. APS and the commission's executive director have disputed it. The commission says the adjuster is a pass-through cost that APS earns no profit on, and that staff and 23 intervenors are auditing it as part of the rate case.

Nobody has ruled on it yet. It's worth watching because it could shape how much of the final increase lands on homes.

What happened to the solar Grid Access Charge?

Here's the short version. In 2024 the commission approved an extra charge for APS customers with rooftop solar. It's billed per kilowatt of panels, and APS's own rate-case testimony puts the typical home at about $2.37 to $2.50 a month.

On June 16, 2026, the Arizona Court of Appeals vacated that decision. The court found the charge was never part of the public notice for APS's earlier rate case, and that a later rehearing didn't fix the problem. It sent the matter back to the commission.

Now the twist. APS's current rate case proposes raising it. In APS's testimony, a typical 10 to 11 kW system would pay about $5.87 to $6.57 a month, depending on the rate plan. APS says the goal is to reduce costs that non-solar customers share. Homes on older “legacy” solar plans don't get a Grid Access Charge change; their base rates rise instead.

The state's solar industry association asked the commission in an August brief to drop the charge entirely. APS and the commission also asked the appeals court to reconsider its June ruling. As of mid-October, we found no public ruling on those requests.

For a solar homeowner, the fixed part of the bill may go down, stay about the same, or go up, depending on how the rate case comes out.

Did the solar export credit change?

Yes. In August the commission approved another 10% cut to the Resource Comparison Proxy, the rate APS pays for solar power you send back to the grid. APS's tariff now lists 5.554 cents per kWh for systems that apply from September 1, 2026. The year before, it was 6.171 cents. Ten percent is the most the rate can drop in one year.

Existing owners care about the next part. Each system's starting rate holds for 10 years from interconnection. After that, APS's tariff says the credit switches to whatever rate is in effect at the time, and it can change year to year.

One catch: adding panels can end the lock. APS treats an increase of 10% or 1 kW-ac, whichever is greater, as a material change. Our Arizona solar rules page has the state's export-credit background, and how net metering changed explains why states moved away from full retail credit.

What does this mean if you're buying or selling a solar home?

This is where the bill and the contract meet. A solar home in APS territory comes with three numbers that matter for the next owner:

• The export rate the system locked in, and when. A system that went live in 2018 has a different credit than one from 2025. APS's tariff says a customer who moves into a home already on this rider keeps that home's rate tier. The 10 years still count from the original interconnection, so a 2018 system's lock runs out around 2028.
• The rate plan on the account. Solar customers in APS territory are on specific plans, and the Grid Access Charge question hangs over them. Pull the last 12 bills and look at the fixed charges line by line.
• The solar payment itself. A lease, PPA or loan payment doesn't care what APS does. If the contract has an escalator, that payment climbs every year whether rates go up 14% or not at all.

That third one trips people up. Sellers often quote savings from the original sales proposal. That proposal was built on export credits and rates from the year it was signed. Some of those numbers no longer exist.

Buyers get handed a “this saves you money” line. Sometimes it does. The only way to know is to put the contract's payment schedule next to the actual bills. Our post on selling a home with leased solar covers the transfer side.

How do you check the numbers on an existing APS solar contract?

Start with three things:

• The full solar contract (lease, PPA, loan or cash purchase paperwork)
• 12 months of APS bills, ideally after the system went live
• The interconnection or permission-to-operate date

Then compare. What does the solar payment add up to over the years left? What did the bills look like? What export credit applies for this system's lock date, and when does it end?

Have the solar contract reviewed before closing, and work with an experienced agent who has handled solar transfers. Don't lean on a chatbot alone for the numbers; scanned contracts and rate tariffs are easy to misread.

How does RateMySolar help?

We read the existing solar contract on a home and give it five letter grades with plain explanations. How we grade describes what each one looks at. You can add the home's power bills, so the report reflects the actual home, not a sales proposal.

Your first upload is free and gives you a locked preview of the report. The full graded report is $49.99 per contract and includes the MLS solar fields and remarks an agent can use in the listing.

Our reports are AI-assisted and partly reliable, so check them against the contract. RateMySolar is not a law firm, and a report is information, not legal or financial advice. For what a contract term means for you legally, talk to a licensed real estate attorney.

Frequently asked questions

How much will APS rates go up?

APS asked for a 13.99% net revenue increase, about $20 a month for a typical home using 1,000 kWh. The commission hasn't voted, and the final number can differ from the request.

When will new APS rates take effect?

APS and the commission expect the case to conclude by the end of 2026. Base rates don't change until the commission votes.

Is the APS solar Grid Access Charge gone?

The Arizona Court of Appeals vacated the current charge on June 16, 2026, and sent it back to the commission. APS's rate case proposes raising it to roughly $6 a month for a typical system, so it isn't settled.

What is the APS solar export rate in 2026?

For systems that apply from September 1, 2026, it's 5.554 cents per kWh. Earlier systems keep the rate they locked in for 10 years from interconnection, then move to the rate in effect at that time.

Does a home buyer keep the seller's APS export rate?

APS's tariff says a customer moving into a home already on the RCP rider keeps that home's rate tier. The 10-year clock doesn't restart, so check the original interconnection date.

Do APS rate changes affect a solar lease or PPA payment?

No. The lease or PPA payment follows the contract, including any yearly escalator. Only the part of the bill from APS changes.

Sources

• APS — APS Rate Case Hearing Begins
• Arizona Attorney General — Court of Appeals vacates the solar surcharge on APS customers (June 16, 2026) and request to investigate the Power Supply Adjuster (Oct. 9, 2026)
• Arizona Corporation Commission — bill credit for APS customers (Oct. 8, 2026) and statement on the Power Supply Adjustor (Oct. 9, 2026)
• APS Rate Rider RCP tariff (export rates, 10-year lock, transfers)
• APS 2025 rate case direct testimony (proposed Grid Access Charge)