By Gabriele Denaro · Published 20 September 2026 · Updated 6 October 2026
Zero-based budgeting means income minus expenses minus savings equals zero. Not because nothing is left, but because every euro already has a category, with savings and investing as lines of their own. Nothing is left unassigned to evaporate into miscellaneous spending.
On €2,400 of income: €800 rent, €150 utilities, €400 food, €150 transport, €100 insurance and other fixed costs, €300 wants, €300 emergency fund and investing, €200 sinking funds. The lines add up to €2,400 and the difference is zero. If groceries cost €440 in practice, you move €40 from wants and the plan still balances.
This is different from tracking what already happened, which is what Patrimony does for your net worth every month. A zero-based budget is a forward-looking plan for income, made before it is spent, and tracking measures what the month did to your overall position. The two work together.
A zero-based budget needs revisiting whenever income or a major expense changes, plus a quick check mid-month so an overspent line is covered by another. That is more work than a fixed rule such as 50/30/20. It pays off for someone who wants precise control and may be overkill for someone who wants a rough, sustainable direction.
You do not need a perfect first month. Begin with your fixed costs and your savings, give the rest a rough split, and adjust at the end of the month with what you learned. After two or three rounds the categories settle.
General educational information, not personal financial, tax or legal advice. It may be incomplete or out of date. Terms of use.