I have 6.

• bank 1, my original that I've been with since I was a teenager. All payments go in, and get distributed out to other accounts from here.

• bank 2 - has a savings account with highest possible interest rate. Using this for long term savings that I'll only dip into as a last-resort for an emergency, and it'll eventually be my house deposit. Also has transaction accounts with some benefits that I use mainly for recurring bills.

• bank 3 - had to set up a transaction account with them to use my preferred share/ETF trading platforms

• bank 4 - got a credit card with them (for points) that I do most of my day to day spending on.

• bank 5 - allows multiple savings accounts with a good interest rate and minimal hoops to jump through. I have separate savings accounts, eg one as a buffer for my shorter term bigger expenses (car rego, dentist or medical etc) and one to store money spent on credit card that I accumulate each month then use to pay it off just before the due date

• bank 6 - another savings and transaction account that I use for luxuries (books, clothes, holidays, etc). I could probably close this one and just use bank 5 instead.