2.6Budget & project costs
The essentials in 30 seconds
- Budget costs the WBS: labor (effort × daily rate), purchases, services, materials — each package has a cost.
- A prudent budget holds a reserve: a contingency reserve sized to uncertainty, because contingencies will occur.
- Reflex: track actual vs plan + estimate remaining spend — detect early, while you can still act.
Running mini-case — Bilal costs his project and owns a reserve
Bilal costs each package (effort × daily rate + a laptop and licenses) and adds up: the total scares the sponsor, who wants to trim it by removing the reserve. Bilal holds firm: with no reserve, the first contingency will blow the budget with no safety net. He proposes monthly actual-vs-plan tracking with remaining spend — the sponsor accepts the reserve and tracking.
Last episode of cases 2.1-2.5 — Bilal closes his planning with the budget.
1. Costing from the WBS
The budget translates the project into money: labor (often the main item), purchases, services, materials, licenses. It is built on the WBS and effort estimates: each package has a cost, whose sum forms the overall budget.
Bilal applies the recipe package by package: estimated effort × daily rate, plus identified purchases and services.
2. Reserve and tracking
A prudent budget is not limited to estimated cost: it includes a contingency reserve, because contingencies will inevitably occur. It is sized by uncertainty.
Tracking actual costs against plan throughout the project detects drifts early — well before it is too late to react. Facing a variance, arbitrate via the triangle: cut scope, draw on the reserve, or request additional budget — never silently cut quality.
🔎 Concrete example — 🔎 Concrete example — Reacting to an overrun
Understand before acting.
Detected variance: where from? (bad estimate? expanded scope? contingency?)
Arbitrate via the triangle: cut scope, draw on the reserve,
or request additional budget — never silently cut quality.Outcome: drifts detected while there is still time.
Reflex: a reserve sized to uncertainty.
Section vocabulary
- Budget
- Quantified estimate of all project costs, often built from the WBS.
Simple example: Bilal's budget: sum of each package's costs + reserve.
What it is not: already-spent actual cost (that's tracking, not budget).
Reflex: no budget without a package-by-package costed WBS.
- Direct / indirect cost
- Direct: attributable to the project (labor, purchases). Indirect: shared overhead (premises, structure).
Simple example: Development days (direct) vs a share of office rent (indirect).
What it is not: the contingency reserve (that's a provision, not an indirect).
Reflex: check applicable indirects are included.
- Contingency reserve
- Amount planned to cover identified contingencies: a prudent budget always holds one.
Simple example: Bilal provisions a reserve sized to the new tool's uncertainty.
What it is not: a hidden cushion to artificially inflate the budget.
Reflex: an owned reserve, sized to uncertainty.
- Actual vs plan
- Comparing spent vs budgeted: reveals cost drifts.
Simple example: End of March: 40% of budget spent for 30% progress — variance to analyze.
What it is not: a comparison done once, at project end.
Reflex: compare regularly, from execution start.
- Remaining spend
- Estimate of what remains to commit to finish: with spent, it gives the forecast final cost.
Simple example: Spent + re-estimated remainder = projected final cost, vs budget.
What it is not: initial budget minus spent (with no re-estimation).
Reflex: re-estimate the remainder, not just subtract.
In practice — In practice — Building and tracking a budget
- From the WBS and estimated effort, cost each package (labor = effort × daily rate + purchases/services).
- Add up to get estimated cost, then add a contingency reserve (a percentage by uncertainty level).
- Set up tracking: regularly compare actual spent cost against budget to date.
- Estimate remaining spend to project final cost: are we drifting? React before it is too late.
Ready-to-say script — defending the reserve to the sponsor (1 min)
"This budget costs each package, plus a reserve for contingencies — a brand-new project always holds some. In return, I give you monthly tracking: actual vs plan and remaining spend. Remove it, and the first contingency puts us in crisis with no safety net."
Say to the sponsor wanting to trim: reserve + tracking for peace of mind.
Copy-paste template — building and tracking my budget
PACKAGE → COST (effort × daily rate + purchases/services): _______________
ESTIMATED TOTAL: _______________
RESERVE (by uncertainty): _______________
TOTAL BUDGET: _______________
TRACKING (actual vs plan to date): _______________
REMAINING SPEND → PROJECTED FINAL COST: _______________Small business / tight budget
A spreadsheet is enough: one row per package, one reserve row, one actual-vs-plan column updated monthly.
Algerian SME
Bilal costs in dinars with his accountant: valued efforts, local purchases, owned reserve — and monthly tracking set.
Internal project (no billing)
Even with no client to bill: costing valued days shows the project's true cost and arbitrates priorities.
Innovative / uncertain project
High uncertainty = wider reserve and close tracking: re-estimate remaining spend at each milestone.
✓ Best practices
- Build the budget from the WBS (cost per package).
- Plan a contingency reserve proportionate to uncertainty.
- Track actual vs plan and project final cost (remaining spend).
✗ Common pitfalls
- A "tight" budget with no reserve at all.
- Comparing actual to plan only at the end (too late).
- Silently cutting quality to hold the budget.
Key takeaways
- The budget costs all work, from the WBS (labor first).
- A prudent budget includes a contingency reserve.
- Tracking actual against plan reveals drifts.
- Remaining spend projects final cost: anticipate rather than suffer.
48h Challenge — apply tomorrow
Cost 3 packages of your WBS (effort × cost + purchases), add up, add an owned reserve (template above). Present the total to someone and defend the reserve.
- I can build a budget from the WBS package by package.
- I can justify a contingency reserve.
- I've costed real packages with tracking planned.
Frequently asked questions
What contingency reserve to plan?
It depends on uncertainty level: a repetitive, well-known project can settle for a small reserve (5–10%), an innovative project demands more. The reserve must match identified risks. What matters is that it exists and is owned: a "tight" budget with no margin slips at the first contingency. A reserve is not a luxury but an honest acknowledgment that uncertainty exists.
How to react to a budget overrun?
First understand the cause (bad estimate? expanded scope? contingency?). Then arbitrate via the triangle: cut scope, draw on the reserve, or request additional budget from the sponsor — never silently cut quality. Detected early through tracking, a variance is corrected; discovered at the end, it becomes a crisis. That is the whole point of regular tracking: turning a nasty surprise into an anticipated decision.
Bilal's sponsor wants to remove the reserve "to lower the budget" and only see accounts at the end. What risk?