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Gestão e Produtividade3 min read

Zero-based budgeting: what I learned by doing, not studying

ZBB isn't a spreadsheet exercise; it's an exercise in habit and power. What I learned implementing it across the group.

When we started implementing zero-based budgeting (ZBB) across the group, I already knew the theory. It's simple: instead of taking last year's budget and adjusting at the margin, you zero everything out and force each expense to justify itself again, from scratch. The difficulty isn't there.

The difficulty is that ZBB isn't a spreadsheet exercise. It's an exercise in habit and in power. When you tell a manager he'll justify every line from zero, you're saying, in practice, that nothing is guaranteed just because it existed. That's uncomfortable — and that's exactly the point.

A few things I learned in practice that no manual told me this clearly:

  • No owner, no cut. Breaking the operation into decision packages only works if each package has a responsible person, first and last name. An orphan package can't be justified or cut — it just survives.
  • The right question isn't "how much does it cost," it's "what happens if it doesn't exist." Everyone learns to defend a cost. The real test is the impact of its absence. When the answer is "nothing relevant," you've found fat.
  • The data has to come from a single source. We pull the history from the ERP (in our case, SAP S/4HANA), not from parallel spreadsheets. The moment each area brings its own number, the discussion becomes about the numbers, not about the choices.
  • ZBB is annual, but the mindset is continuous. The gain isn't in the document approved in December. It's in no longer treating recurring expense as untouchable all year long.

The best side effect of ZBB isn't financial, it's cultural: it forces the company to know why it does what it does. In a company that grows by acquisition and integrates different operations, that's worth gold — each company that joins arrives with its own "truths" about what's essential, and ZBB is an honest way to test them.

It isn't painless and it isn't fast. But the first time a manager comes to you to cut his own cost — because he understood it doesn't hold up — you realize the method took.

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