We have a checking account at Wells Fargo that we rarely use. We keep it just for the occasional B&M service discussed in another recent thread (notary, large cash withdrawal/deposit, etc).
Most of our normal banking activity utilizes our Fidelity cash management account, including checking, bill-pay, direct deposit, ATM, check deposit, and cash-back CC. Not sure I'd call that a "bank account" though. It's a Fidelity brokerage account with all cash management features enabled.
We have an online savings account at Ally where we keep a small cash allocation as part of our investment portfolio.
I guess that's 3... or maybe 2. I could probably consolidate everything to the Fidelity CMA, but what we have is easy to manage.