Rules library

Vault or Flow in 10 Seconds (Decision Tree)

Stop guessing. Use this 10-second decision tree to classify any expense as Vault (bill) or Flow (spending) and follow the next step instantly.

Stop debating every purchase. Use this quick decision tree to classify any expense as Vault (bills) or Flow (spending) in ~10 seconds.


The 10-second decision tree

  • Question 1: If I don’t pay this, do I risk losing housing/essential services/coverage? Yes → Vault. (Use What Counts as a Bill and Bills vs Spending.)
  • Question 2: Is it “essential-ish” but flexible (health, repairs, work needs, travel, gifts)? Maybe → Gray Zone. Apply the rule on Gray Zone Expenses and decide once.
  • Everything else: Flow. It’s spending. Give it a limit and enjoy it without guilt.

If it’s Vault: do this next

If it’s Flow: do this next


If you’re new (or restarting), don’t overthink it. Set up the system once, then only make simple decisions.

Put it into practice

Make the system yours.

Return to Start here