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Education·24 May 2026·5 min read

The personal budget — the first lesson we're not taught in school

What comes in, what goes out, what's left. It sounds trivial, but it's the most important financial habit of life. How to keep a budget — and how to practice it without stress.

The personal budget — the first lesson we're not taught in school
Image: CC0 · Wikimedia Commons

A personal budget is a simple sum: income minus expenses. If something is left, you save. If it goes negative, you borrow or cut expenses. That's it. And yet many adults have never done this exercise.

The 50/30/20 rule

A popular rule: 50% of income for needs (food, rent), 30% for wants (fun, hobbies), 20% for savings and debt. It's not a law, but it's an excellent starting point for not spending everything that comes in.

Practice with KOSR

In Kosron Bank you have accounts, cards and transfers — exactly the tools to simulate a budget: you "allocate" your income, pay "expenses", set aside in a savings account. Kids and teens build the habit without the risk of making mistakes with real money.

It's not how much you earn, but how much you keep. The budget is the map that shows you where the money goes.