Ultra Mobile PayGo is one of the cheapest ways to hold a real US carrier number, not a VoIP one. It runs on the T-Mobile network and costs $3 per 30 days as of September 2026. Many non-residents use it purely as a "parking" number for SMS verification and bank 2FA, and receive codes over Wi-Fi Calling while abroad.
This guide covers buying, activating, paying from abroad and keeping the number alive. PayGo details change, so confirm the current terms at ultramobile.com before you buy.
Plan at a glance
| Item | PayGo (as of September 2026) |
|---|---|
| Price | $3 per 30 days |
| Included | 100 minutes, 100 texts, 100 MB data |
| Overage | $0.03/min, $0.01/text, $0.03/MB |
| Network | T-Mobile (4G LTE / 5G) |
| Roaming | Voice/SMS paid from wallet balance. Reported rates start around $0.25/min and a few cents per text. No data roaming |
| Wi-Fi Calling | Supported. Must be enabled in your account and on the phone |
| Cancellation | Account and number cancelled if no payment within 60 days of the last one |
At 100 texts a month, receiving verification codes will rarely cost anything extra.
Step 1: Get a SIM or a pre-activated line
There are a few routes. Reports vary on which ones work from abroad:
- Official SIM kit. Ultra sells PayGo kits in some US retail stores (including some T-Mobile stores) and online. Kits are generally physical SIMs.
- Marketplace kits. PayGo SIMs, including "pre-activated" lines with several months prepaid, are sold on marketplaces such as eBay. Buy only from sellers with a strong history. The seller controls the setup until you take the account over, so change the account PIN and email right away.
- Via a friend in the US. Someone in the US buys and activates the SIM, then mails it or hands it over.
Step 2: Activate
- Insert the SIM into an unlocked phone.
- Go to Ultra's PayGo activation page (my.ultramobile.com/paygo/activation), enter the SIM number, and choose a number by area code or ZIP.
- Create your online account with an email you control. Set a strong password and an account PIN, and write the PIN down.
- Add funds to the PayGo wallet and confirm the plan is active.
- Send a text to another phone to confirm the line works.
If you use a pre-activated line, log in and update the account email and PIN to your own right away.
Step 3: Turn on Wi-Fi Calling
Wi-Fi Calling lets the SIM connect to T-Mobile's network through any internet connection. Texts and calls then arrive abroad without roaming charges.
- In your Ultra account, enable Wi-Fi Calling and enter the E911 address it asks for.
- On iPhone, go to Settings → Phone (or Cellular) → Wi-Fi Calling and turn it on for the Ultra line. On Android, open the SIM settings.
- Test it. Turn on airplane mode, reconnect Wi-Fi, and send yourself a text. The status bar should show "Wi-Fi" next to the carrier name.
Ideally, set this up before you leave the US or while the line is new. For dual-SIM tips and troubleshooting, see Wi-Fi Calling abroad.
Step 4: Pay from abroad
- Auto-Renew. In the account, add a credit or debit card and turn on Auto-Renew so the wallet refills every month.
- Foreign cards. Reports vary. Some users pay with non-US cards, others are declined. Try your card while you still have time left on the line.
- Prepaid months. Some marketplace kits come with 6–12 months of credit, which lowers the risk if a payment fails.
- Refill PINs. Refill vouchers are sold by third parties. Buy only from reputable sellers.
Keep-alive checklist
| When | Action |
|---|---|
| Every cycle (30 days) | Confirm the $3 renewed and the wallet has a small buffer |
| Monthly | Send one text and receive one code over Wi-Fi Calling |
| After phone updates / SIM swaps | Re-check that Wi-Fi Calling is on |
| Every quarter | Log in to the Ultra account and trigger a bank 2FA code |
Converting to eSIM
Some users move an active PayGo line from physical SIM to eSIM through Ultra's account or support. Before you try:
- Make sure you know your account PIN and can receive email at the account address.
- Do it while you have good internet and, if possible, a backup way to receive codes.
- If the transfer fails partway, you may need Ultra support to issue a new eSIM. That is harder to do from abroad.
Pitfalls
- Roaming data is not included. Keep mobile data for the Ultra line off abroad. Use Wi-Fi or another SIM for data.
- Short codes. Some banks send codes from short codes (5–6 digit senders). Delivery over Wi-Fi Calling is usually fine, but a few users report gaps. Test with your own bank.
- Locked phones. A phone locked to another carrier will reject the SIM.
- Account takeover. Protect the Ultra account with a unique password and PIN. Your number is only as safe as the account behind it.
FAQ
Can I receive codes in mainland China? Only through Wi-Fi Calling, and results depend on your network. Test it before you rely on it. Follow local network rules.
Does receiving texts cost anything? Received texts count toward your 100 texts. The overage is $0.01 per text.
Can I port the number out later? Prepaid numbers can usually be ported to another US carrier. Ask Ultra for your account number and port-out PIN.
