An American moving to New Zealand discovered a critical oversight that could lock him out of his financial accounts: two-factor authentication from US banks doesn't work with most international phone services.<br><br>"What are the best options for mobile numbers—including porting over my current US based number—to a cheaper service, which will allow me to do Two Factor Authentication?" he asked on r/digitalnomad. His current plan costs over $100 monthly but includes unlimited service in both Canada and New Zealand.<br><br>The problem is deceptively simple: US banks require US phone numbers for verification codes. Once you cancel your US number and get a local SIM, those authentication texts stop working. And without 2FA access, you can't log into accounts—even from a verified device.<br><br>As one commenter noted: "Many Burner or other proxy-ish services aren't accepted for security purposes." Banks specifically block VoIP numbers, temporary numbers, and most online phone services.<br><br>This isn't a minor inconvenience. It's a potential complete lockout from banking, credit cards, investment accounts, and government services. For digital nomads and expats, maintaining a reliable US number becomes essential infrastructure.<br><br>The r/digitalnomad community has developed several solutions:<br><br>Google Voice—Free US number that receives SMS and works for many (but not all) banks. Requires keeping a US number active to port to Google Voice initially. Some banks block it, others accept it. The service works internationally but may have limitations with certain authentication systems.<br><br>T-Mobile International Plans—The $50-70 monthly plans include international roaming. Many expats maintain these specifically for banking access. Some report that data speeds internationally are throttled but SMS works fine for 2FA.<br><br>Ultra Mobile or Mint Mobile—Budget MVNOs running on T-Mobile's network. Plans as low as $15-30 monthly. The key is keeping the number active with minimal usage rather than canceling and losing it.<br><br>US Mobile or Tello—Pay-per-use options where you can maintain a number for under $10 monthly if you only receive SMS. Some digital nomads keep one of these as a dedicated 2FA line.<br><br>NumberBarn or other number parking services—Port your US number to a service that holds it for $2-5 monthly, then forward texts to email or an app. Works for some authentication systems but not all.<br><br>The consensus: . Port your main number to Google Voice (one-time $20 fee), then maintain an inexpensive prepaid US line as backup for services that block Google Voice.<br><br>Several travelers mentioned discovering the problem only after moving abroad and finding themselves locked out. one commenter wrote. <br><br>The strategic timing matters: , not after arrival in your new country. Test that all your important accounts work with your chosen solution. Update banking contact information while you still have easy access.<br><br>Beyond 2FA, maintaining a US number helps with: requiring US contact information. to US addresses. from credit bureaus or government agencies. for US contacts who may not want to call international numbers.<br><br>As the original poster noted, his current $100+ monthly plan seems excessive for maintaining banking access. But .<br><br>For Americans planning extended international stays, the recommendation is clear: secure your US number situation before departure. .