Week one in France can be a challenge for US phone users before you even sign your lease. Roaming bills spike, bank SMS never arrives, or an app rejects a VoIP number. If you need to keep US phone number abroad for banking, plan before you fly.
Quick answer: Keep a cheap US mobile carrier eSIM (typically around $5 to $10 a month depending on taxes and plan, for example Tello) with Wi-Fi Calling on before departure, and add a real French (+33) contract for local admin. Google Voice is free for casual use, but it is not a reliable replacement for a carrier mobile number for financial accounts. Travel data-only eSIMs do not give you a French number. See the FCC number porting guide and Google Voice porting help.
Pairs with our French phone contract guide and French bank account guide.
Why you need to keep US phone number abroad
US banks, brokerages, and tax portals usually send codes to a US mobile number. A French (+33) line rarely replaces that path. Common week-one failures: roaming bill shock or extended international roaming restrictions, silent 2FA failure after a VoIP port, and apps that refuse virtual numbers.
Where possible, avoid SMS-based authentication. Many banks now support authenticator apps, passkeys, hardware security keys, or app push notifications, which are generally more secure and less dependent on a US mobile number abroad.
Google Voice, cheap US eSIM, or other VoIP?
Google Voice is not a reliable replacement for a carrier mobile number for financial accounts. Some institutions accept it for certain flows; others reject VoIP entirely or only for high-risk actions.
| Option | Best for | Watch-outs |
|---|---|---|
| Google Voice | Casual US texts and some non-financial codes | VoIP; inconsistent bank support |
| Cheap US MVNO eSIM (e.g. Tello) | Bank SMS that need a real mobile line | Typically around $5 to $10/month; enable Wi-Fi Calling before you leave |
| Sonetel / Skype / Telio-style VoIP | US presence for calls, lighter SMS use | Often weaker for bank 2FA; test first |
| French contract (+33) | Lease, French bank, Ameli, home Wi-Fi | Does not replace US bank SMS |
Sweet spot for many movers: a low-cost US mobile eSIM for financial codes that need a carrier-style number, plus a French plan for daily life. Some people also keep Sonetel for calls and lighter SMS. It is not perfect for every bank flow, but it can get the job done for everyday US contact once you have tested what your accounts accept. See moving to France for Americans.
Myths about Google Voice for expats in France
Forum threads often say Google Voice works for everything. Many banks use telecom databases to determine whether a number is mobile or VoIP. Google Voice is VoIP. Users frequently report inconsistent Google Voice and VoIP support at places like Chase, Bank of America, Wells Fargo, Capital One, PayPal, Venmo, and Vanguard. A number that works for login may later fail on password resets or high-risk transfers.
It is generally much easier and less risky to complete a port before leaving the United States while your existing carrier service is active. Google Voice typically accepts ports from eligible US mobile numbers (not landlines or many business numbers). After a port, telecom databases do not always update immediately, so a number that works for SMS at first may later be recognized as VoIP by some services.
How to set up US and French lines before you move
Set your US strategy while you are still home, then add a true French number after arrival.
- Choose a cheap US MVNO eSIM with SMS and Wi-Fi Calling (typically around $5 to $10 a month depending on taxes and plan). Port if you want the same digits, and finish while the old carrier is still active when you can.
- Turn on Wi-Fi Calling (and Backup Calling if supported). Test a bank login before you fly. Prefer authenticator apps, push login, or a security key wherever offered.
- After landing, get a French mobile contract with a real +33 number. Travel eSIMs are usually data-only and do not unlock a lease or French bank file.
- Use the French line for local data and French admin. Keep the US eSIM for bank SMS that still need a mobile line. On many modern dual-SIM phones, the US line can use the French SIM’s data for Wi-Fi Calling-style service (“Backup Calling”), although support varies by phone and carrier.
- Optional: keep Sonetel or similar for casual calls if your tests show it works for those accounts.
Illustrative example: Google Voice and a blocked transfer
Fictional example based on common expat experiences: Sarah cancels an $80 Verizon plan the day before flying to Lyon and ports to Google Voice. Weeks later Chase refuses SMS for a €3,000 apartment transfer. Support calls fail automated checks. She needs family help in the US, faces a multi-day hold, and nearly loses the apartment. A cheap US carrier eSIM before departure, plus non-SMS login where available, would have cost far less.
Next: opening a French bank account and renting in France.
Common mistakes when you keep US phone number abroad
- Relying on Google Voice alone for bank 2FA
- Leaving SMS as your only authentication method when better options exist
- Porting or cancelling your US line from France when you could finish setup before departure
- Assuming a travel data eSIM replaces a French +33 contract
- Leaving a full-price US major-carrier plan on roaming “just in case”
- Skipping a test login after you enable Wi-Fi Calling
FAQ
Can I port my US number to Google Voice after I arrive in France?
Sometimes, but it is generally much easier and less risky before you leave while your US carrier is still active. Google Voice typically ports eligible US mobile numbers only, not landlines or many business numbers.
Why did bank 2FA work for a while on Google Voice and then stop?
After a port, telecom databases do not always update immediately. A number that initially works for SMS may later be recognized as VoIP by some services.
Is Google Voice enough for Chase, PayPal, or Vanguard?
Do not count on it. Users report mixed results. Keep a real US mobile number for accounts that still require SMS, and prefer app or key-based 2FA when offered.
What is the cheapest reliable way to keep US phone number abroad for SMS?
A low-cost US MVNO eSIM with Wi-Fi Calling is how many people keep US phone number abroad for SMS. Test with your banks before you leave. Pricing is typically around $5 to $10 a month depending on taxes and plan.
Do I still need a French phone number if I have a travel eSIM?
Yes for most relocation admin. Data-only travel eSIMs do not give +33. See our French phone contract guide.
Will Wi-Fi Calling receive US bank texts from France for free?
In many cases, yes. If Wi-Fi Calling is active, incoming SMS generally works over Wi-Fi (or on some phones via the other SIM’s data) without international roaming charges. Check your carrier’s policy and test before you leave.
How Relocora helps you stay in the right order
Relocora does not sell SIMs or port numbers. It sequences US eSIM and Wi-Fi Calling before departure, then French +33, then bank and lease tasks on your checklist. Store carrier contracts, porting PINs, and SIM ICCID details in the Document Vault. Ask the AI Coach to explain French carrier messages or draft a cancellation letter pattern (information only).