What happens when you switch carriers
Switching carriers means moving your phone service from one company to another — AT&T, Verizon, T-Mobile, a regional carrier, or a prepaid reseller. You keep your phone number if you request a port, which transfers your number to the new carrier. The process typically takes one to three business days, though your old service stays active until the port completes. You'll need your account number and PIN from your current carrier before you start.
Most people switch to save money, get better coverage in their area, or move to a carrier that offers a phone they want. The actual switching process is straightforward, but timing matters — if you switch mid-month, you may owe both carriers for partial service. Some carriers charge early termination fees if you're still under contract, though month-to-month plans have become standard.
Key Takeaways
- Request your account number and PIN from your current carrier before you contact the new one — you'll need both to port your number.
- Porting your number takes one to three business days, and your old service stays active until the transfer is complete.
- Check whether your phone works on the new carrier's network by entering your model number on their website, because not all phones work on all networks.
- If you're under contract or have a device payment plan, contact your current carrier to find out what fees or obligations apply before you leave.
- Switching mid-month usually means paying both carriers for partial service, so timing your switch to a billing cycle can save money.
Get your account details from your current carrier
Before you contact a new carrier, call or log into your current carrier's website and write down your account number and PIN (or password). These are the two pieces of information the new carrier will ask for to port your number. Your account number appears on your bill or in your account settings online. Your PIN is usually a four-digit code you set up when you opened the account, or the last four digits of your Social Security number if you never created one.
While you're gathering information, ask your current carrier whether you have an early termination fee, an active device payment plan, or any other obligation that would cost money to leave. Some carriers waive these fees during promotional periods, and it's worth asking. Write down the answer so you can factor it into your decision.
Check that your phone will work on the new network
Not every phone works on every carrier's network. The major carriers — Verizon, AT&T, and T-Mobile — use different technologies, though most modern phones work across all three. Prepaid carriers and regional carriers may have more limited phone compatibility. Before you switch, go to the new carrier's website and enter your phone's model number in their compatibility checker. If your phone isn't compatible, you'll need to buy a new one or choose a different carrier.
If you need a new phone, compare the cost of buying one outright against the new carrier's device payment plans or promotions. Some carriers offer discounts or bill credits when you switch, which can offset the cost of a new phone. Ask the new carrier what deals are currently available for people switching from another carrier.
Choose your plan and contact the new carrier
Decide which plan you want on the new carrier — this includes your monthly cost, data allowance, and any add-ons like international service or device protection. Once you've decided, contact the new carrier through their website, phone, or a retail store. Tell them you want to port your number from your current carrier. They'll ask for your account number and PIN, and they'll verify that the number can be transferred.
The new carrier will give you a confirmation number and tell you when the port will complete. Write this down. They'll also give you a new SIM card (if you need one) or activate your phone on their network. Your old carrier's service will stop working once the port is complete, so don't cancel your old account yourself — let the port process handle it.
What to expect during the transfer
The port usually takes one to three business days. During this time, your old carrier's service stays active, so you can still make and receive calls and texts. Once the port completes, your phone will stop working on the old carrier's network and will start working on the new one. You may see a brief gap of a few minutes where you can't make calls, but this is normal.
If the port takes longer than three business days, contact the new carrier to check the status. Occasionally a port gets stuck because of a mismatch in account information or because the old carrier didn't process it correctly. The new carrier can usually resolve this by contacting your old carrier on your behalf. Keep your confirmation number handy so you can reference it when you call.
Timing your switch to avoid double charges
If you switch mid-month, you'll typically owe your old carrier for service through the end of your billing cycle, and you'll owe the new carrier for service starting on the day the port completes. This means you'll pay both carriers for partial months. To avoid this, try to time your switch to the day before your billing cycle ends, so your old carrier's final bill covers service through the end of the month and your new carrier's first bill starts on the first day of the next month.
Check your current carrier's billing date by logging into your account or calling customer service. If your billing cycle ends on the 15th, for example, request the port to complete on the 14th. This won't always be possible — the port date depends on when the new carrier processes your request — but it's worth asking the new carrier if they can time the transfer to your billing cycle.
What to do if something goes wrong
If your number doesn't port successfully, the new carrier will usually contact you to explain why. Common reasons include a mismatch between the account number or PIN you provided and what the old carrier has on file, or a flag on your account that prevents porting (like an unpaid balance). Contact your old carrier to fix the issue, then ask the new carrier to try the port again.
If you can't get your number to port after multiple attempts, you have the option to keep your old number and start fresh with a new number on the new carrier. This is less common, but it's an alternative if the port process breaks down. You can also file a complaint with the Federal Communications Commission if you believe the old carrier is blocking the port illegally, though this is rare.
Frequently Asked Questions
Can I keep my phone number when I switch carriers?
Yes, if you request a port. When you contact the new carrier, tell them you want to port your existing number. They'll handle the transfer from your old carrier. The process takes one to three business days, and your old service stays active until it's complete.
Do I have to buy a new phone when I switch?
Only if your current phone doesn't work on the new carrier's network. Check the new carrier's website with your phone's model number before you switch. If it's compatible, you can bring it with you. If not, you'll need to buy a new one or choose a different carrier.
What if I'm still paying for my phone on my current carrier?
You can still switch carriers, but you'll need to finish paying off the phone or pay the remaining balance in full when you leave. Contact your current carrier to find out the payoff amount. Some new carriers offer bill credits or promotions that can help cover this cost.
Will I lose service during the switch?
Your old carrier's service stays active until the port completes, which usually takes one to three business days. You may experience a brief gap of a few minutes once the port finishes and your phone switches to the new network, but this is normal and temporary.
What if my old carrier charges an early termination fee?
You'll owe it when you leave, unless the carrier waives it. Some carriers waive these fees during promotions, so it's worth asking. A few new carriers offer bill credits to cover early termination fees from your old carrier, so compare offers before you decide to switch.