That's the wrong question to ask. There are no financial institutions that have proper 2FA. I don't know of a single bank in the US that uses any standard 2FA. They all use SMS. Recently, I found that you can make paypal (US) use TOTP 2FA with a workaround. I recommend everyone to do that.

My snarky answer is use an MVNO that will both show up as the base carrier to any searching online/number lookups, and has completely useless clueless terrible support that either couldn't or wouldn't redirect like this.

Assuming you even have to use SMS, get some weird walmart mobile service that you can't even really call for support.

It's security through obscurity but they often literally wont let you port your number out without absurd gymnastics, the support people don't know how, their crappy web based management system the CSRs use doesn't have a button, etc.