How to charge your phone during a power outage

The short answer

To charge your phone during a power outage, first cut its use: turn on Low Power Mode or Battery Saver, dim the screen and text instead of calling. Then recharge from a charged power bank, a power station, a laptop's USB port, a car parked outdoors, or a hand-crank or solar radio.

Ready.gov calls smartphones a vital tool for getting emergency alerts and warnings, and tells households to have an emergency charging option for every phone. The work starts before the outage: Ready.gov advises fully charging all devices before severe weather and keeping a backup power source on hand.

Step one: keep the phone charged longer

Every percent you save is a percent you do not have to generate. Ready.gov says to save battery power by minimizing device use and to switch the phone to low power mode or airplane mode.

iPhone: Low Power Mode

On iPhone 15 and later, open Settings, tap Battery, tap Power Mode and turn on Low Power Mode. On iPhone 14 and earlier, it is under Settings, then Battery. Apple says it reduces display brightness, sets Auto-Lock to 30 seconds, and turns off email fetch, Background App Refresh and automatic downloads. One catch: Apple says Low Power Mode turns off when you charge to 80% or higher, so turn it back on after each top-up during an outage.

Android: Battery Saver

On most Android phones, open Settings, tap Battery, then Battery Saver. Google also suggests letting the screen turn off sooner, lowering brightness, turning on dark theme and restricting apps with high battery use. Menu names vary by manufacturer.

• Close apps that use GPS, streaming video and games.
• Use airplane mode when you do not need the network, and turn it off at set times to check messages and alerts.
• Use a lantern or flashlight, not the phone's flashlight. See best emergency lights for a power outage.
• Get news from a battery or crank radio instead of streaming it. See best emergency radios.

Text instead of calling

Ready.gov says mobile networks can become overwhelmed during emergencies, making calls hard to place, and that text messages need less bandwidth, so they go through more reliably when many people are on their phones. Ready.gov also suggests creating a group chat for family and friends before a disaster. In a life-threatening emergency, call 911.

Ways to charge a phone without power

Power banks: the mAh to phone-charge math

Power banks are rated in mAh at their internal cell voltage, and some energy is lost converting to USB output. Our planning assumption (not a manufacturer figure) is that roughly two-thirds of the rated mAh reaches the phone.

1. 01Find your phone's battery size in mAh from the maker's specs. We use 4,000 mAh here as an example.
2. 02Multiply the bank's rating by 0.65: a 24,000 mAh bank such as the Anker 737 gives about 15,600 mAh.
3. 03Divide by the phone battery: 15,600 ÷ 4,000 is about 3.9 full charges.
4. 04A 9,600 mAh bank such as the Goal Zero Venture 35 gives about 6,200 mAh, or about 1.5 charges of the same phone.
5. 05Multiply by people and days: 2 phones × 1 charge a day × 3 days = 6 charges, which is more than one 24,000 mAh bank.

Our radios and power banks kit page compares power banks in more depth.

Power stations and solar

A portable power station is a large battery with USB and AC outlets. A 1,000 Wh-class unit such as the Anker SOLIX C1000 can charge a household's phones for many days and still run lights and a fridge. It can be recharged from solar panels. Size one with how to get electricity during a power outage or the backup power calculator. Goal Zero says its Venture 35 recharges from a Nomad 10 solar panel in about 6 to 12 hours.

Your car

Ready.gov suggests keeping a portable phone charger in the car at all times. A car's USB port or a 12 V adapter can charge phones while driving or idling, but only outdoors.

Hand-crank and solar radios

A crank radio keeps you informed and can add a little charge in a pinch. Expect very little: Ready America says one minute of cranking its kit's Emergency Power Station gives 2 minutes of talk time on a cell phone. A radio with a built-in power bank, such as the Midland ER310PRO with 10,000 mAh, is more useful because you charge it before the outage and crank or solar only tops it up.

Research-based picks to keep phones charged

A big USB-C bank for the household, a rugged small bank, a radio with a built-in battery, and a power station for long outages. Picks are based on manufacturer specs; we do not test products.

No. 1Power bank

Anker 737 Power Bank (PowerCore 24K)

Best for: High-capacity USB-C bank that can charge a laptop

• 24,000 mAh
• 140W max output
• 2× USB-C + 1× USB-A
• Smart digital display
• 630 g (22.22 oz)

Tradeoffs

• · No solar input; recharge from wall or USB-C
• · Heavy for a pocket

Check price on AmazonRead the full reviewSpecs: manufacturer page, checked Nov 1, 2026

No. 2Power bank

Goal Zero Venture 35 Power Bank

Best for: Rugged, waterproof bank you can recharge from a solar panel

• 9,600 mAh / 35.52 Wh
• IP67 waterproof (1 m for 30 min, port door closed)
• USB-C PD 18W in/out plus USB-A out (15W)
• Solar recharge with Goal Zero Nomad 10 (about 6-12 hrs); USB-C about 3 hrs
• 50-lumen flashlight; 10.12 oz; operating range 32-113°F

Tradeoffs

• · Small capacity for a whole household; Goal Zero says to recharge it every 3-6 months in storage
• · 18W is too slow for most laptops; solar panel sold separately

Check price on AmazonRead the full reviewSpecs: manufacturer page, checked Nov 1, 2026

No. 3Emergency radio

Midland ER310PRO Emergency Crank Radio with Power Bank

Best for: Keeping phones charged as well as hearing weather alerts

• Power: USB-C, solar or hand crank; 10,000 mAh lithium-ion battery
• 200+ hours of radio play (manufacturer figure); USB-C full charge in 6 to 8 hours
• NOAA weather alerts (not SAME), AM/FM, Bluetooth streaming, clock and temperature display
• USB-A phone output (5 V, 2.1 A): a full charge powers most smartphones 2 to 3 times (Midland FAQ)
• Cree LED flashlight with SOS strobe; ultrasonic dog whistle

Tradeoffs

• · No AA battery backup, unlike the ER310; no water-resistance rating stated.
• · Midland's FAQ says solar extends a charge but will not revive a flat battery

Check price on AmazonRead the full reviewSpecs: manufacturer page, checked Nov 1, 2026

No. 4Power station

Anker SOLIX C1000 Portable Power Station

Best for: Running a fridge, lights, phones and a CPAP through a one- or two-day outage

• 1,056 Wh capacity (up to 2,112 Wh with the matching expansion battery)
• 1,800 W continuous / 2,400 W surge AC output
• LiFePO4 battery chemistry
• 6 AC outlets
• 28.44 lb

Tradeoff

• · At about 28 lb it is a carry-to-the-car unit, not a grab-and-go bag item.

Check price on AmazonRead the full reviewSpecs: manufacturer page, checked Nov 1, 2026

A phone power plan for a 3-day outage

1. 01Before the storm: charge every phone, power bank, radio and laptop to full.
2. 02Hour one: turn on Low Power Mode or Battery Saver on every phone, and send one group text with your plan.
3. 03Keep one adult's phone at a reserve level for emergency calls; let others run lower.
4. 04Recharge from power banks once a day, in the evening, so phones are full overnight.
5. 05Recharge power banks from a power station, a car parked outdoors or solar during daylight.
6. 06Write key phone numbers on paper in case a phone dies. Ready.gov's Make a Plan page has a fillable family communication card.

For everything else to stock before the next outage, see what to buy before a power outage and the blackout checklist. If you rely on AA devices, see best rechargeable batteries.