I have 6 accounts:
A for income, ex. when I get a check I put 80% here
B taxes, when I get a check I put 20% here (taxes in Poland are 18%)
then:
C for business expenses, I know how much I spend each month, and I wire that amount each month from A
D personal account - whatever is left in A after business expenses, I wire here
Finally:
E, joint account with my partner, I know how much we spend each month and I wire that from D -> E
F, saving account for myself. Whatever is left in D at the end of the month, I put here
ING lets me manage all these accounts from their app, and wire money instantly from one to the other. All these accounts cost about $2/mo. each, but if there's enough action (ex., if you spend at least $500/mo.) the price drops to 0.
This setup is useful to not go splurge every time you get paid.