APS Summer Rates Start May 1, 2026: What Changes and How to Prepare

On May 1, 2026, APS flips from winter to summer rate season. On the Saver Choice Plus plan — the one most Arizona solar and battery owners are on — the peak rate jumps from $0.2145/kWh to $0.3439/kWh. That's a 60% increase on every kWh you burn between 4 and 7 PM weekdays. If your habits don't change, your May bill will.

Full APS Winter vs Summer Rate Comparison

All rates below reflect the Saver Choice Plus Time-of-Use plan, the default for most residential APS customers and the most common plan for solar and battery owners. Other APS plans (Saver Choice, Premier Choice, Lite Choice) have their own seasonal adjustments — check your bill or the APS rate sheet for your exact plan.

Rates sourced from the 2026 APS residential rate schedule. Rates as of April 2026 and subject to change; your bill may include additional riders and adjustments not shown above.

What the Switch Actually Costs in Dollars

The headline number ("60% more") sounds abstract. Here's what it looks like on an actual bill. These examples isolate the winter-to-summer rate shift . They assume identical usage patterns, so the only thing changing is the per-kWh price.

Example 1: Light peak user (2 kWh/weekday during 4–7 PM)

• Winter peak cost: 2 kWh × $0.2145 × 22 weekdays = $9.44/month
• Summer peak cost: 2 kWh × $0.3439 × 22 weekdays = $15.13/month
• Monthly difference from peak alone: +$5.69

Example 2: Average AZ home (10 kWh/weekday during 4–7 PM)

• Winter peak cost: 10 × $0.2145 × 22 = $47.19/month
• Summer peak cost: 10 × $0.3439 × 22 = $75.66/month
• Monthly difference from peak alone: +$28.47

Example 3: High peak user (20 kWh/weekday — big house + pool + dryer)

• Winter peak cost: 20 × $0.2145 × 22 = $94.38/month
• Summer peak cost: 20 × $0.3439 × 22 = $151.32/month
• Monthly difference from peak alone: +$56.94

And that's just the peak window. Off-peak hours also bump up 19%, so your overnight AC cooling and late-evening laundry also get slightly more expensive. The super off-peak 10 AM–3 PM window is the only time of day that doesn't get more expensive, which is the entire point of the next section. For your actual numbers, plug your usage into the APS bill calculator.

Why APS Rates Go Up in Summer

Arizona summer peaks are some of the most punishing grid demand anywhere in the US. When 1.3 million APS homes simultaneously cool 110°F homes starting at 4 PM, demand spikes past what the cheap baseload generators can cover. APS fills the gap with natural-gas "peaker" plants that are 3–5x more expensive per kWh to run. Summer peak rates are simply that cost getting passed through to TOU customers in the window when you're driving it.

The super off-peak window (10 AM–3 PM) doesn't get more expensive because that's when utility-scale and rooftop solar floods the grid. AZ has so much midday solar that the wholesale price briefly goes negative most sunny days. APS gets cheap power at noon and expensive power at 5 PM — the rate schedule reflects that.

7 Things to Do Before May 1

You have roughly two weeks. These are ordered by dollars-saved-per-minute-spent.

1. Set your thermostat to pre-cool to 73–74°F by 3 PM

This is the single highest-impact move. And the single reason a smart thermostat pays for itself in one summer. Pre-cool your home while electricity is at $0.0935/kWh, then let it drift up to 78–80°F during the peak window. The house acts as a thermal battery. A well-insulated home can coast through the full 4–7 PM window without the AC kicking on at all.

Savings: $40–$80/month in summer. Run the exact numbers for your home in our AZ pre-cooling savings calculator. If your current thermostat can't schedule by TOU period, see our best smart thermostat for APS TOU rates guide.

2. Reprogram the pool pump to finish by 3 PM

Pool pumps are one of the biggest hidden peak-hour costs in AZ homes. A 1.5 HP pump pulling 1.5 kW that runs 8 hours/day costs ~$69/month on winter peak but ~$93/month on summer peak if it runs during the 4–7 PM window. Set the timer to run during super off-peak (10 AM–3 PM). Same runtime, half the cost.

3. Move dishwasher and dryer cycles out of the peak window

An electric dryer load is roughly 4 kWh. That's $0.86 on winter peak but $1.38 on summer peak — versus $0.37 during super off-peak. Delay-start on your dishwasher and dryer costs nothing. Shifting 4 loads a week saves roughly $16/month in summer.

4. Reschedule EV charging

Never charge an EV during 4–7 PM after May 1. A Level 2 charger pulls 7–10 kW. A full 50 kWh Model 3 charge during summer peak is $17.20. The same charge during super off-peak is $4.68 — a $12.52 swing per charge. Set your car or charger to start at 10 PM or noon (weekdays only). Our EV charging cost calculator shows the exact monthly difference for your vehicle.

5. Add window film to west-facing windows

West-facing windows take the brunt of 3–7 PM sun — exactly when the grid is most expensive. Blocking that heat reduces how hard your AC has to work during peak. Window film is ~$15–30 per roll at Amazon, installs DIY in 30 minutes, and can cut AC load by 10–15% during the peak window.

6. Find hidden peak-hour energy drains

An energy monitor on your breaker panel shows exactly which circuits are running during peak. Arizona homeowners routinely find $20–50/month of surprise peak-hour usage they didn't know about — an old AC unit short-cycling, a pool heater left on, a server rack or 3D printer running during peak. Ten minutes with an energy monitor will pay back the device in one bill.

7. If you have solar or a battery — recheck your setup

Summer is when self-consumption and battery arbitrage pay off most. Check that:

• Your solar inverter is set to maximize self-consumption, not pure export (export credit is ~$0.076/kWh; summer peak retail is $0.3439/kWh — 4.5x more valuable used on-site than sold).
• Your battery is set to charge during super off-peak (10 AM–3 PM) and discharge during peak (4–7 PM). That's a $0.2504/kWh summer arbitrage spread, nearly double what winter offered.
• You're enrolled in APS Cool Rewards / VPP, which pays $350–$400/year for letting APS dispatch your battery during summer grid events.

How the May 1 Switch Changes the Math for Batteries

A 13.5 kWh battery (like a Tesla Powerwall 3 or EcoFlow DELTA Pro 3) shifting a full charge from super off-peak to peak earns:

• Winter: 13.5 kWh × ($0.2145 − $0.0935) = $1.63/day arbitrage = ~$49/month
• Summer: 13.5 kWh × ($0.3439 − $0.0935) = $3.38/day arbitrage = ~$101/month

Summer arbitrage is 2x what winter offered. That's before VPP earnings, demand response payments, or self-consumption of solar production. If you were on the fence about battery storage, the May 1 rate flip is the reason to run the numbers now. Our battery ROI calculator and Powerwall payback calculator model summer and winter rates separately. Non-solar homeowners should read our APS battery ROI without solar breakdown — the summer spread is what makes standalone batteries pencil out in Arizona.

What Doesn't Change on May 1

• Peak hours stay 4–7 PM weekdays. The window doesn't shift; only the price changes.
• No peak on weekends or APS holidays. Saturday and Sunday stay off-peak all day. See APS off-peak hours and holidays for the full 2026 holiday list.
• Super off-peak stays $0.0935/kWh. The 10 AM–3 PM window is the only part of the rate schedule that stays the same price year-round.
• Export credits for existing solar customers. If you're under the RCP export credit, your rate is locked for 10 years from interconnection. May 1 doesn't touch it.
• The service charge. APS's fixed monthly charge is the same year-round.

Bottom Line

May 1 is the most expensive date on the APS calendar. Peak rates climb 60% overnight, and Arizona's summer heat means that window is also when you want to use the most electricity. The two-week runway between now and May 1 is enough time to set up pre-cooling, reprogram pumps and dryers, shift EV charging, and add $50–$100 of cheap insulation-style fixes that pay back in the first bill. Anyone who does nothing will pay $30–$80 more per month for the same usage. That's the cost of missing the date.