What Is Zero-Based Budgeting?
Zero-based budgeting (ZBB) is a budgeting method in which every expense must be justified from scratch for each new period, starting from a "zero base" rather than adjusting the prior period's budget. Nothing is carried over automatically — each cost has to earn its place.
What zero-based budgeting is and why it matters
Traditional (incremental) budgeting starts with last period's numbers and adjusts up or down, which quietly preserves spending that may no longer be needed. Zero-based budgeting resets to zero and requires managers to justify every line as if building the budget for the first time. The payoff is disciplined spending — it exposes waste, forces prioritization, and ties resources to current goals rather than history. The cost is effort: ZBB is far more time-consuming to prepare, so businesses often apply it periodically or to discretionary categories rather than every line, every period.
A worked example
A department's marketing budget last year was $200,000. Under incremental budgeting, next year might simply be set at $210,000 (a 5% bump). Under zero-based budgeting, the manager starts at $0 and justifies each activity: $60,000 for content, $50,000 for events, $40,000 for paid ads, and $30,000 for tools — $180,000 total, with a scrapped $20,000 sponsorship that no longer delivers results dropped entirely. ZBB surfaced a cut that incremental budgeting would have preserved.
How firms handle it today
Firms help clients run zero-based budgeting exercises — building budgets from activities and justifications rather than history — typically on a periodic basis given the effort involved, to reset spending discipline.
Related terms
- Budget
- Forecasting
- Operating expenses
- Overhead
- Variance
FAQ
What's the difference between zero-based and traditional budgeting?
Traditional budgeting adjusts the prior period's budget; zero-based budgeting builds from zero, justifying every expense anew.
What are the benefits of zero-based budgeting?
It exposes waste, forces prioritization, and aligns spending with current goals rather than historical habit.
What's the downside of ZBB?
It's time-consuming to prepare, which is why many businesses apply it periodically or to discretionary spending rather than every line each period.