Setting up your first savings rule

Saving fails for a boring reason: it requires a decision, every month, at the exact moment when spending the money is more appealing than not spending it.

Rules exist to remove that decision. You make it once, in a calm moment, and then it repeats without asking you again.

Here's how to set up the first one properly.

Start with the paycheck, not the leftovers

The most common way people save is to move whatever is left at the end of the month. This almost never works, because there's almost never anything left. Spending expands to fill the available balance — that's not a character flaw, it's just what happens when the constraint is invisible.

Reverse the order. The rule should fire when money arrives, not when it's about to run out. If your salary lands on the 28th, the rule runs on the 28th.

Pick a number you'll actually keep

Everyone's instinct is to be ambitious. The number that survives is the one that doesn't hurt.

We suggest starting at 5% of net income. It's small enough that you won't notice it, which is exactly the point — a rule you cancel in month three has done nothing. A rule at 5% that runs for two years has done a great deal.

You can raise it later, and most people do. In our data, users who start at 5% end up averaging 11% within eighteen months. Users who start at 15% average 4%, because most of them turn the rule off and never turn it back on.

Give the money a destination and a name

An unnamed savings balance is a slush fund, and slush funds get spent. A named goal is much stickier — "Emergency fund" and "Japan, April" behave completely differently from "Savings", even when they're the same account.

Name it after the thing, not the amount. "Three months of expenses" beats "$6,000", because the first one tells you why you're doing it.

Set the floor before you set the rule

This is the step people skip, and it's the one that causes rules to get switched off.

Decide the balance below which the rule should not fire. If your current account drops under that number on payday, the transfer is skipped rather than pushing you toward an overdraft.

A rule that occasionally causes a shortfall gets deleted after the second time. A rule with a floor survives indefinitely, because it never puts you in a position where turning it off feels necessary.

What happens next

On payday, Cassis works out the amount and tells you to move it. You confirm the transfer in your own banking app — we never move money ourselves, and we never will.

That last step takes about fifteen seconds and it's deliberate. The confirmation is the difference between a tool that helps you save and a tool with access to your accounts. We'd rather have the fifteen seconds.

The two mistakes

The first is too many rules at once. People set up five goals in the first session, split their income into fragments, and can't tell whether any of it is working. Start with one. Add a second when the first has run for three months without you thinking about it.

The second is treating the rule as permanent. Income changes, rent goes up, priorities move. Look at your rules twice a year — the same cadence as the subscription audit, and ideally the same sitting.

Beyond that, the correct amount of attention to pay a savings rule is none. That's what it's for.