Zero-based budgeting starts every budget at zero and funds only what can be justified. List each decision package with its cost and priority to see which requests fit within the available budget and where the funding line falls.
How it works
Build a zero-based budget from decision packages: rank each request, fund them in priority order up to the available budget, and compare the result with prior-year spending.
Sort packages by priority rank
Cumulative cost = running total of package costs in rank order
Fund each package while cumulative funding ≤ Available budget
Unfunded requests = Total requested − Funded budgetCommon uses
- Annual budget cycles that challenge legacy spending
- Cost-reduction and turnaround programs
- Allocating discretionary and project funding
Worked example
The calculator above opens with this example. Change any input to see the results update instantly, or select Reset to return to these figures.
| Decision packages | Core financial close & reporting | 420,000 | 1 | 405,000 Payroll processing | 180,000 | 2 | 176,000 Audit & compliance | 145,000 | 3 | 150,000 FP&A forecasting platform | 96,000 | 4 | 0 Treasury management system | 72,000 | 5 | 68,000 Process automation (RPA) | 110,000 | 6 | 0 Staff training program | 38,000 | 7 | 45,000 Consulting: cost study | 85,000 | 8 | 120,000 |
| Available budget (funding limit) | $1,000,000 |
| Last package that does not fit | Leave unfunded |
| Funded budget | $951,000 |
| Total requested | $1,146,000 |
| Unfunded requests | $195,000 |
| Packages fully funded | 6 |
| Unallocated budget | $49,000 |
| Change vs. prior year | ($13,000) |
The funding line falls at “Process automation (RPA)”. Packages below it need a business case, a lower-cost alternative or deferral.
Interpreting the results
- Each package should state its purpose, cost, measurable benefit and the consequence of not funding it.
- Rank packages across departments, not within them, so funding goes to the highest organizational priorities.
- Packages just below the funding line are the natural candidates for scaled-down alternatives.
Frequently asked questions
What is zero-based budgeting?
Zero-based budgeting requires every expense to be justified for each new period, rather than starting from the prior year’s budget. Activities are grouped into decision packages, ranked by priority and funded until the available budget is used.
What is a decision package?
A decision package describes an activity or request: its purpose, cost, expected benefits and the consequences of not funding it. Packages are often prepared at several funding levels so decision-makers can choose a reduced version.
Is zero-based budgeting worth the effort?
Full zero-based budgeting is time-consuming, so many organizations apply it to discretionary spending or rotate it across departments every few years. It is most valuable when costs have drifted upward without scrutiny.
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