They might just truncate the password during login as well. I was able to login to my online banking using only the first five digits of my password not more than 3 years ago.. They fixed it in the meantime but I'm still worried.

> Trial and error?

Bingo. Super frustrating.

See also this comment: https://news.ycombinator.com/item?id=24827031

I once had a bank that used substr(tolower(input_password), 0, 8) as the actual password.

That happened to me many years ago with Microsoft logins. They were truncating passwords to 12 characters and my generated 16-character passwords never worked. I kept resetting them over and over until I did a Google search for Microsoft password requirements and found out that they were being truncated.

That was likely fixed a long time ago, but I'm still wary of increasing my Microsoft passwords past 12 characters.

I had it happen a few times. Usually I would reset it a few times until realizing that it's obviously not saving the password I'm entering, at which point I would try a setting a shorter one.

T-Mobile did this to me a few years ago. Don't know if they still do, but I couldn't believe anyone thought that was ok.