Note, I have not tried this, but just saw this so am posting for those who are looking for options to receive authentication codes from US institutions. I was actually looking for a travel data sim.

Saily, which does travel e-sims just started offering US numbers for $0.99/month. The add on plans for calls and texts for Thailand start at $0.99 / 30 days. Only 5 minutes and 5 SMS. So about $1.98/month combined but it is 5 days short on the plan side each year. However, the number is separate from the plan since this is intended for traveling to different countries, so the plan can be changed. The plan can also just end and then be started back up again when needed or bumped up to more texts. Which could work in someone did things infrequently.

Read through the terms of service and search for phone for details. What I can see is make sure there is no lapse in paying for the number or they can't guarantee you can get that number back. Because it goes into quarantine and can't be reissued to anyone for some regulated period. The terms say you can sign up for a number subscription for 1 month, 3 months, 6 months or 12 months. But I can't see any way to do a subscription for more than 1 month, but autopay can be set up. You have to provide id through the app to get the number, so I think this is no different than any other cell number in how it works. One other thing to note is there's no data so if your bank sends messages that include anything other than text, they won't come through. Maybe would if you also have a Saily data plan. I don't think they do wifi calling or texting since they started as travel data sims.

Link and screen snips below.

Website:

Get an eSIM with a phone number | Saily

I use SlyNumber app with a real phone number.

The SMS is sent directly to the app on my Thailand phone.

Can purchase a USA phone number through the Numero app at €18 a year and can receive unlimited incoming SMS messages from banks and financial institutions in the USA. The messages with the codes come right into the app on your smartphone.

Google Voice. It's for US customers but works via Wifi, Mobile. Never missed a text.

12 minutes ago, J Branche said:

Google Voice. It's for US customers but works via Wifi, Mobile. Never missed a text.

I've been using that a lot, but I just found out that Schwab does not send texts to Google voice.

24 minutes ago, eddyod said:

I've been using that a lot, but I just found out that Schwab does not send texts to Google voice.

Many of those "voice" apps have been rejected lately.

The key is to find a service that gives you a real phone number.

Excuse my ignorance, but why would you need a US Ph# ?

My financial institution sends authenication code to my Thai Ph# every so often when wanting an ID check.

For that it is worth, I just signed up for Numero. The app is useless and the web interface is also useless. I tried signing up for Slynumber and that works well. Maybe it is me? Now I need to make sure Schwab can send texts to it. Thanks for the help.

4 hours ago, Ricohoc said:

I use SlyNumber app with a real phone number.

The SMS is sent directly to the app on my Thailand phone.

My AI says slyNumber is likely to not work with my US banks. You have had good luck with it? It says the same about Numero as well.

Edited July 25Jul 25 by wimpy

21 minutes ago, KhunLA said:

Excuse my ignorance, but why would you need a US Ph# ?

My financial institution sends authenication code to my Thai Ph# every so often when wanting an ID check.

Some US financial institutions. Don’t.

Not sure what yours could be, but even my US Asian bank won’t accept any other than U.S. phone numbers.

5 minutes ago, OneManShow said:

Some US financial institutions. Don’t.

Not sure what yours could be, but even my US Asian bank won’t accept any other than U.S. phone numbers.

Same, both US banks I have only send to US numbers.

11 minutes ago, Dcheech said:

Same, both US banks I have only send to US numbers.

Some financial ins. Have more options for OTP, some phone number only. Last time I was there I ordered a RSA code generator from my bank (free), it works for wire transfers ass well (large amount). It will work about 4 year.

37 minutes ago, OneManShow said:

Some US financial institutions. Don’t.

Not sure what yours could be, but even my US Asian bank won’t accept any other than U.S. phone numbers.

Fidelity Investments, as I haven't used a 'bank' in over 45 yrs, as useless, and charge you for every little thing. Amazed people still use, when Fid. & Charles Scwabs are available.

You folks need to change financial institutions. They make money off your money, and shouldn't be charging you for anything.

Anyone using Tello? Were you able to activate from outside the US?

5 hours ago, Ricohoc said:

I use SlyNumber app with a real phone number.

The SMS is sent directly to the app on my Thailand phone.

Is SlyNumber an eSIM or just an application?

Fidelity Investments, as I haven't used a 'bank' in over 45 yrs, as useless, and charge you for every little thing. Amazed people still use, when Fid. & Charles Scwabs are available.

You folks need to change financial institutions. They make money off your money, and shouldn't be charging you for anything.

Not sure what charge you’re referring to. I did not mention any. 🤔 it’s about OTP and ways possible to receive it.

Many institutions are not accepting VOIP numbers, but many do. If yours won’t send a code usually there is a call option and that works fine for me. They call my VoIP number and give me the verification code. You just have to play around and see what works. It’s not as easy as it used to be. Too many issues I gather. Good luck.

4 hours ago, KhunLA said:

Excuse my ignorance, but why would you need a US Ph# ?

My financial institution sends authenication code to my Thai Ph# every so often when wanting an ID check.

Agreed. I regularly get an sms code sent directly to my Thai phone when they want to check it is me signing on to a US financial institution on my computer here in Thailand. Instantaneously sent and confirmation it is me signing in.

I've tried a few VOIP options over the years and even used family (located in USA) numbers and had OTP's relayed to me via Messinger. All worked to one degree or another but not without hiccups. Almost 5 years ago I started using Mint mobile which piggy backs T-Mobile network. It has worked flawlessly (so far) for receiving OTPs from my bank and USA Credit Card company. On occasion when I return to USA it's available to me for making calls and includes data (data is not required to make a call - it's a real phone number). It's an e-sim that I was able to install while in Thailand. The downside is the cost is about $200/year. Worth its weight in gold when I needed an OTP to complete a transaction. I realize that the cost is not for everyone, but it is an option that has worked 100% of the time for me.

23 minutes ago, kimothai said:

I've tried a few VOIP options over the years and even used family (located in USA) numbers and had OTP's relayed to me via Messinger. All worked to one degree or another but not without hiccups. Almost 5 years ago I started using Mint mobile which piggy backs T-Mobile network. It has worked flawlessly (so far) for receiving OTPs from my bank and USA Credit Card company. On occasion when I return to USA it's available to me for making calls and includes data (data is not required to make a call - it's a real phone number). It's an e-sim that I was able to install while in Thailand. The downside is the cost is about $200/year. Worth its weight in gold when I needed an OTP to complete a transaction. I realize that the cost is not for everyone, but it is an option that has worked 100% of the time for me.

Whoa, $200 a year, just call your card provider if transaction denied, as got to be cheaper. How many times do you get denied. Myself, maybe once a year, and only when if not a normal transaction history for me. Such as buying a drone on AliExpress, which I haven't done in long time. Usual use for ATM or hotel booking.

Last week or so, I got denied using ATM/VISA @ BBL, and called VISA, and they didn't deny it, or even show the transaction. So it was BBL software oops, or they turned it off, due to better rate 😂

Past 10 ish days, got denied 2X again, 'contact bank', didn't bother, and it was BBL oops again. As if my bank/VISA denied, they'd have to unblock it, and since working without calling, know it wasn't on my end.

Every now & then, FID will ask for a verification, as I hadn't signed in since beginning of the year, so they asked last month, and haven't asked since. Even though I've used debit card to book hotels here, TH a few times this year.

6 hours ago, KhunLA said:

Excuse my ignorance, but why would you need a US Ph# ?

My financial institution sends authenication code to my Thai Ph# every so often when wanting an ID check.

I am unable to load my Thai phone number with the bank that has my MasterCard in the US. They only accept US phone numbers with an area code.

My other financial institutions and even PayPal accepts my Thai phone number.

5 hours ago, wimpy said:

My AI says slyNumber is likely to not work with my US banks. You have had good luck with it? It says the same about Numero as well.

It works for me.

5 hours ago, KhunLA said:

Fidelity Investments, as I haven't used a 'bank' in over 45 yrs, as useless, and charge you for every little thing. Amazed people still use, when Fid. & Charles Scwabs are available.

You folks need to change financial institutions. They make money off your money, and shouldn't be charging you for anything.

Fidelity and Schwab are my banks of choice in the US. I haven't had a need with Fidelity, but I can contact Schwab in numerous ways damn near 24 hours a day (phone, email, internal messaging, etc.) and it's with a HUMAN. NEVER an issue when needing to get something done quickly, efficiently and effectively. They're helpful beyond belief for a large financial institution.

Ditched CapOne and citibank and Chase long ago.

5 hours ago, connda said:

Is SlyNumber an eSIM or just an application?

App with a real phone number. Not VOIP.

5 hours ago, wimpy said:

Anyone using Tello? Were you able to activate from outside the US?

Tello can only be activated in the US through the US towers that they use.

The down side is that even if you get someone to activate Tello for you in the US on a phone just for that purpose, and you run into a glitch overseas and need to reactivate it, you won't be able to reactivate it in Thailand. You'd have to send the phone back to the US to get someone to activate it for you again. That was a hoop that I was unwilling to jump through.

2 hours ago, KhunLA said:

Whoa, $200 a year, just call your card provider if transaction denied, as got to be cheaper. How many times do you get denied. Myself, maybe once a year, and only when if not a normal transaction history for me. Such as buying a drone on AliExpress, which I haven't done in long time. Usual use for ATM or hotel booking.

Last week or so, I got denied using ATM/VISA @ BBL, and called VISA, and they didn't deny it, or even show the transaction. So it was BBL software oops, or they turned it off, due to better rate 😂

Past 10 ish days, got denied 2X again, 'contact bank', didn't bother, and it was BBL oops again. As if my bank/VISA denied, they'd have to unblock it, and since working without calling, know it wasn't on my end.

Every now & then, FID will ask for a verification, as I hadn't signed in since beginning of the year, so they asked last month, and haven't asked since. Even though I've used debit card to book hotels here, TH a few times this year.

Since having a real USA number, I never get denied because I can always verify an OTP. It's not just about credit cards; it's also about banking. I maintain multiple accounts because as banking rules change in the USA the person who usually comes out on the short end of the stick is the person with a foreign address. I like to keep backup accounts (actually, I keep backup to the backups) because all my incomes are via auto deposit. You are right in that it is cheaper to just call the financial institution to get the problem sorted, but I prefer to keep things simple and not have to do all that. I've seen multiple threads on this same topic where people are trying to use VOIP connections or other methods (that are inexpensive), and all seem to have drawbacks of one type or another (when dealing with financials). Even though I only go back to USA occasionally, it is nice being connected (with data) when I land at the airport. For me, the cost (which may be prohibitive for some) dwarfs the convenience of having a real number.

7 hours ago, eddyod said:

For that it is worth, I just signed up for Numero. The app is useless and the web interface is also useless. I tried signing up for Slynumber and that works well. Maybe it is me? Now I need to make sure Schwab can send texts to it. Thanks for the help.

I’ve been using Numero for a few years now and haven’t had any problems with it. It works with Chase, PayPal, Fidelity, Schwab, and probably a few others. I think PayPal, and possibly Chase, might have rejected the number when I tried to add it myself. However, after calling customer service and asking them to add it manually, it worked fine for receiving the authentication codes.

The confusing part of the Numero app is the interface. At the bottom of the screen there’s a Messages icon, which is the second icon from the left. Sometimes authentication codes don’t show up there. Instead, tap the bell icon in the top right corner of the app, and the messages with the codes will always be there. I have no idea why it works that way, but that’s been my experience.

1 hour ago, Ricohoc said:

My other financial institutions and even PayPal accepts my Thai phone number.

I believe if you have a US based PayPal account, their system will only accept a US phone number.

Some financial institutions in the US will accept an overseas phone number, but most of them won't because their systems are only set up for sending SMS messages to domestic phone numbers.

1 hour ago, Ricohoc said:

Tello

can only be activated in the US through the US towers that they use.

The down side is that even if you get someone to activate

Tello

for you in the US on a phone just for that purpose, and you run into a glitch overseas and need to reactivate it, you won't be able to reactivate it in Thailand. You'd have to send the phone back to the US to get someone to activate it for you again. That was a hoop that I was unwilling to jump through.

Gemini said the following about Tello, but I haven't tried it because a number with Tello will cost you $60 a year whereas a US number from Numero only costs €17.99 a year and, from my experience, it works with all US financial institutions that I've tried using it with.

From Gemini:

Officially, Tello states on their website that you must be physically located in the US to activate a new line.

Technically, that official requirement is routinely bypassed from overseas by routing the initial activation signal through Wi-Fi calling.

Official Policy vs Technical Reality

Official Stance: Tello claims first time activation requires connecting to a US cell tower.

Actual Reality: Users activate Tello eSIMs from outside the US every day. The activation handshake completes over an internet connection rather than a physical cell tower.

How to Complete the Overseas Activation:

1. Log into your account on a web browser before scanning the QR code.

2. Navigate to My Settings and register a valid US address under Emergency E911 Address.

3. Connect your phone to Wi-Fi.

4. Scan the eSIM QR code provided in your Tello dashboard.

5. Enable Wi-Fi Calling in your device settings.

14 minutes ago, FriscoKid said:

Gemini said the following about Tello, but I haven't tried it because a number with Tello will cost you $60 a year whereas a US number from Numero only costs €17.99 a year and, from my experience, it works with all US financial institutions that I've tried using it with.

From Gemini:

Officially, Tello states on their website that you must be physically located in the US to activate a new line.

Technically, that official requirement is routinely bypassed from overseas by routing the initial activation signal through Wi-Fi calling.

Official Policy vs Technical Reality

Official Stance: Tello claims first time activation requires connecting to a US cell tower.

Actual Reality: Users activate Tello eSIMs from outside the US every day. The activation handshake completes over an internet connection rather than a physical cell tower.

How to Complete the Overseas Activation:

1. Log into your account on a web browser before scanning the QR code.

2. Navigate to My Settings and register a valid US address under Emergency E911 Address.

3. Connect your phone to Wi-Fi.

4. Scan the eSIM QR code provided in your Tello dashboard.

5. Enable Wi-Fi Calling in your device settings.

I can only go by what Tello agents were repeatedly adamant about. They refused to acknowledge any other way, so I left it behind with no regrets.