I did that (created a new business online account and had Chase merge all personal cards into that login) 6-7 years ago and subsequently closed all my business card accounts which (a few months later) resulted in losing all on-line access. Required a long telephone conversation with Chase to re-establish a personal online profile. For the past couple of years, with multiple personal cards and (again) multiple business cards, I’ve found it easier and more efficient to have 2 different login profiles, one personal and one business.

With my most recent Chase business card a few months ago, my 3rd Chase business card at the time, I could not add it to my online profile and when it was added by Chase it was segregated online from my other Chase business cards. Turns out there was a 1 digit typo* in my SSN for that card, required multiple phone calls (to learn a SSN can only be corrected in person) and multiple visits to a branch to correct.

I’m not familiar with “Flex card” but it’s very quick and simple to “combine” personal and business UR points, having 2 different login profiles is not a hindrance in that regard.

(*It’s still a mystery to me as to how Chase could approve me for a card and open an account and add it to my online profile when that card had an incorrect SSN. Chase has given me several different explanations, including the typo occurred after account opening when it was being added to my online profile. (Why would that require hand-typing a SSN, seems it would just be a few clicks of a mouse?). Doesn’t speak very well for Chase’s identification and verification and security procedures.)