What a US international code phone number is and why car rental companies need it
A US international code phone number is your regular US phone number formatted so someone outside the country can reach you. When you rent a car in another country, the rental company needs this number to contact you about your reservation, pickup details, or any changes to your booking. The format adds the country code (+1) before your 10-digit number, so a number like 555-123-4567 becomes +1-555-123-4567.
International car rental companies require a contact number during booking because they operate across time zones and need a way to reach you if something goes wrong — your reservation gets cancelled, the car class you booked is unavailable, or they need to confirm your arrival time. Without a working number they can actually dial, they may cancel your reservation or charge you a no-show fee even if you show up in person.
The key difference from a domestic number is that the +1 prefix tells phone systems outside the US how to route the call. Without it, a rental agent in Spain or Japan cannot dial your number directly from their phone.
Key Takeaways
- US international format is +1 followed by your 10-digit phone number, and rental companies need this to contact you about your reservation.
- Your regular US cell phone will receive calls and texts at this number even when you are abroad, though international roaming charges may explore.
- If you do not have a US phone number, you can provide the rental company's local office number or your hotel number as an alternative contact.
- Always enter your number with the +1 prefix on international rental websites, because some systems reject numbers without it.
- Test that your number works before your trip by having someone call or text you from abroad, or by calling your own number from an international dialing app.
How to format your US number for international car rentals
Start with your 10-digit US phone number. If it is 555-123-4567, remove the hyphens and add +1 at the beginning: +15551234567. Some rental websites display it with spaces or hyphens for readability — +1-555-123-4567 or +1 555 123 4567 — but the digits themselves are the same.
When you enter your number on an international rental website, look for a field that says "country code" or "international number". Select United States from a dropdown menu if one appears, and enter your number without the +1 if the system adds it automatically. If you are unsure whether to include the +1, include it — most systems recognize and accept it.
Write down your number in +1 format before your trip and keep it in your phone or on paper. You may need to give it verbally to a rental agent at the counter, and having it memorized or written down prevents mistakes.
Whether your US cell phone will work when you receive calls abroad
Your US cell phone will receive calls and text messages at your US number from anywhere in the world, as long as your phone has a signal and your service plan allows it. Most US carriers include incoming calls and texts in your regular plan at no extra charge, even when you are abroad — you do not need to do anything special to receive them.
However, your carrier may charge you for using data, sending texts, or making outgoing calls while abroad. Before your trip, contact your carrier to understand what international roaming costs. Many carriers offer temporary international plans for $10 to $15 per day that include calls, texts, and data. If you do not want to pay roaming charges, you can turn off cellular data and rely on WiFi, and you will still receive calls and texts over your regular connection.
If you are staying in one country for an extended time, consider buying a local SIM card for that country. You will have a local phone number, but your US number will still work for receiving calls — they will straightforward route to voicemail unless you set up call forwarding through your US carrier first.
What to do if you do not have a US phone number
If you are a visitor to the US or do not have an active US cell phone, you have several options for providing a contact number to the rental company. The simplest is to give them the phone number of your hotel or accommodation, since they can reach you there during business hours. Write down the hotel's number and country code before you book.
You can also provide the rental company's local office number in the country where you are picking up the car. They can reach their own office, and the staff there can find you or leave a message. Some rental companies allow you to list multiple contact numbers, so you can provide your hotel, a friend's US number, or an international calling app number as a backup.
If you have a US-based friend or family member, you can list their number and ask them to relay messages to you. Let the rental company know this is an emergency contact, not your direct line. Before your trip, make sure whoever you list as a contact knows they may receive calls about your reservation and how to reach you.
Common mistakes when entering your number on rental websites
The most common error is forgetting the +1 prefix entirely. Some international websites require it; others reject numbers that include it. If your first attempt fails, try the opposite format — if you entered +15551234567 and got an error, try 15551234567 without the plus sign, or try 5551234567 without the country code.
Another mistake is including parentheses or extra hyphens. Stick to the format +1-555-123-4567 or +15551234567 with no other punctuation. If a website has separate fields for country code, area code, and number, enter them in the correct boxes rather than typing the whole thing in one field.
Do not include a leading 1 if the system already added the country code. Some websites show a dropdown for country, then ask you to enter your number — in that case, enter only the 10-digit number, not 1-555-123-4567.
Testing your number before your trip
Before you travel, verify that your number works for international calls. Ask a friend or family member to call or text you from their phone, or use an international calling app like Skype, WhatsApp, or Google Voice to call yourself. If the call goes through, your number is set up correctly.
If you are using a calling app, test it from the country where you will be renting the car if possible. read the app, set it up, and make a test call while you still have time to troubleshoot. Check that your carrier's international roaming is turned on if you plan to use your cell phone abroad.
Contact your rental company a day or two before pickup and confirm they have your correct number on file. Ask them to send you a confirmation text or email — this tells you whether they can reach you and gives you a chance to correct any errors before you arrive.
Alternative contact methods for car rental companies
Most international car rental companies accept email as a backup contact method. During booking, provide an email address you check regularly. Many companies will send you a confirmation email with your reservation details, and they may contact you by email if there are changes to your booking.
Some rental companies offer messaging through their website or app. If you book through their site, you may be able to message them directly through your account. This is useful if you do not want to rely on phone calls or texts, especially if you are concerned about international roaming charges.
WhatsApp and other messaging apps are increasingly common for rental company communication, particularly in Europe and Latin America. When you book, ask whether the company uses WhatsApp or another messaging service. If they do, add their number to your contacts before your trip so you can reach them quickly if needed.
Frequently Asked Questions
Will I be charged if the rental company calls me while I am abroad?
No. Incoming calls to your US number are typically included in your plan at no extra charge, even when you are abroad. You only pay for outgoing calls, texts you send, or data you use. Check with your carrier before your trip to confirm their specific international roaming policy.
Can I use a Google Voice number or Skype number for a car rental reservation?
Some rental companies accept them, but many do not. Google Voice and Skype numbers are not traditional US phone numbers, and some systems flag them as invalid. Call the rental company before booking to ask whether they accept these numbers, or provide a traditional cell phone number as your primary contact.
What if I lose my phone while traveling and cannot receive calls?
Contact the rental company when ready using email, their website, or a phone at your hotel. Provide them with an alternative contact number — your hotel, a friend's number, or a local number where you can be reached. Most companies will work with you to reschedule or resolve issues if you reach out proactively.
Do I need to do anything special to my phone plan before renting a car internationally?
Contact your carrier and ask about international roaming rates for calls, texts, and data in the country where you will be. Ask whether they offer a temporary international plan. You do not need to change your number or set up anything special — your existing US number will work — but understanding the costs helps you decide whether to use WiFi or purchase a local SIM card.
Can the rental company reach me if I turn off my phone during my trip?
No. If your phone is off, calls will go to voicemail. If you plan to be unreachable for a period, let the rental company know in advance and provide an alternative contact method, such as your hotel number or a backup person they can reach.