What if my phone is locked and I didn't realize it before I left?

Call your home carrier's international support line (Google the number before you fly and save it). They can sometimes unlock it remotely while you're abroad if your account is in good standing. Otherwise, you'll need to rent a portable WiFi device at the airport or rely on hotel and café WiFi for your trip.

Do I need to delete anything from my phone before installing a local SIM?

No. Your apps, photos, and data stay on the phone. Only your phone number changes temporarily. iMessage and FaceTime may need a few minutes to reactivate using your email instead of your phone number. WhatsApp will work normally.

Can I use the same SIM card if I visit multiple countries?

Depends on the region. European SIMs work across the entire EU without roaming charges. Asian SIMs usually don't work across borders. If you're visiting multiple countries, look for regional SIMs (like 'Asia SIM' or 'Europe SIM') sold at airports, or plan to buy a new SIM in each country.

What happens to my two-factor authentication codes?

If you use SMS for 2FA, you won't receive codes sent to your home number while using a local SIM. Before you leave, switch important accounts (bank, email) to app-based authentication like Google Authenticator or Authy. Or keep your home SIM in a second phone if you have one.

Should I get an eSIM instead?

If your phone supports eSIM (iPhone XS or newer, Google Pixel 3 or newer, Samsung Galaxy S20 or newer), yes — it's easier. You buy data online before you fly, scan a QR code, and you're connected when you land. No store visit needed. Costs about the same as airport physical SIMs. Airalo and Holafly are reliable eSIM providers.

How do I top up data if I run out?

Most tourist SIMs can be recharged at convenience stores (7-Eleven in Asia, Oxxo in Mexico, tobacco shops in Europe). Tell the clerk your carrier name and phone number. They'll add credit to your account. Or use the carrier's app if you set it up at purchase.

How to Get a Local SIM Card When You Land

Buy a prepaid SIM card at the airport immediately after clearing customs, or wait until you reach the city center for better rates. Bring your passport, an unlocked phone, and small bills in local currency. Expect to pay $10-40 for 7-30 days of data depending on the country.

Check if your phone is unlocked before you leave. Contact your carrier at least 2 weeks before departure. Ask them to unlock your device. Most carriers unlock phones that are paid off or out of contract within 24-48 hours. Test it with a friend's SIM if possible. An unlocked iPhone will show 'No SIM restrictions' under Settings > General > About > Carrier Lock.
Research carrier options for your destination. Google '[country name] prepaid SIM cards for tourists' before you fly. Note which carriers offer airport kiosks and which require city stores. Read recent reviews on coverage quality. In most countries, the largest carrier has the best coverage but costs 20-30% more than competitors.
Decide between airport or city purchase. Airport SIM cards cost 50-100% more but save you 2-4 hours of wandering without navigation. Worth it if you arrive at night, need a rideshare immediately, or are nervous about finding a store. City stores offer better rates and more plan options. Look for official carrier stores, not resellers in tourist areas.
Bring your passport and cash. Most countries legally require ID for SIM registration. Bring your physical passport — a photo usually won't work. Have $20-50 in local currency in small bills. Airport kiosks often don't take cards, and city stores may charge a fee for card payments.
Ask for a tourist data package. Say 'I need a prepaid SIM with data for [X] days.' Specify data amount: 10-20GB for normal use, 30-50GB if you're uploading photos or using maps constantly. Most tourist plans include unlimited local calls and texts. Skip international calling — use WhatsApp instead.
Watch them install and test it. Don't leave the counter until they've installed the SIM, activated it, and you've successfully loaded a website. Save the store receipt and write down the phone number they assign you. Take a photo of any activation instructions in the local language.
Keep your home SIM safe. Put your original SIM in your phone case, passport holder, or a small ziplock bag in your day bag. Don't leave it in your checked luggage. You'll need it when you land back home. Physical SIMs are tiny and easy to lose.

What if my phone is locked and I didn't realize it before I left?: Call your home carrier's international support line (Google the number before you fly and save it). They can sometimes unlock it remotely while you're abroad if your account is in good standing. Otherwise, you'll need to rent a portable WiFi device at the airport or rely on hotel and café WiFi for your trip.
Do I need to delete anything from my phone before installing a local SIM?: No. Your apps, photos, and data stay on the phone. Only your phone number changes temporarily. iMessage and FaceTime may need a few minutes to reactivate using your email instead of your phone number. WhatsApp will work normally.
Can I use the same SIM card if I visit multiple countries?: Depends on the region. European SIMs work across the entire EU without roaming charges. Asian SIMs usually don't work across borders. If you're visiting multiple countries, look for regional SIMs (like 'Asia SIM' or 'Europe SIM') sold at airports, or plan to buy a new SIM in each country.
What happens to my two-factor authentication codes?: If you use SMS for 2FA, you won't receive codes sent to your home number while using a local SIM. Before you leave, switch important accounts (bank, email) to app-based authentication like Google Authenticator or Authy. Or keep your home SIM in a second phone if you have one.
Should I get an eSIM instead?: If your phone supports eSIM (iPhone XS or newer, Google Pixel 3 or newer, Samsung Galaxy S20 or newer), yes — it's easier. You buy data online before you fly, scan a QR code, and you're connected when you land. No store visit needed. Costs about the same as airport physical SIMs. Airalo and Holafly are reliable eSIM providers.
How do I top up data if I run out?: Most tourist SIMs can be recharged at convenience stores (7-Eleven in Asia, Oxxo in Mexico, tobacco shops in Europe). Tell the clerk your carrier name and phone number. They'll add credit to your account. Or use the carrier's app if you set it up at purchase.