Budget Variance Analysis Skill
Produces a complete variance analysis from numbers through to root cause explanation and management commentary.
Required Inputs
- Actuals and budget figures (paste as table or describe line by line)
- Period (month / quarter / YTD)
- Materiality threshold (e.g. £10k or 5%)
- Known reasons for variances (if any)
- Audience (CFO / board / management / auditor)
Output Structure
1. Variance Summary Table
| Line Item | Budget | Actual | Variance £ | Variance % | F/A |
|---|---|---|---|---|---|
| Revenue | |||||
| Cost of Sales | |||||
| Gross Profit | |||||
| Opex | |||||
| EBITDA |
F = Favourable | A = Adverse
2. Material Variance Commentary
For each variance above threshold:
[Line item] — £[amount] F/A ([%])
- Root cause: [Specific explanation — not "timing" without detail]
- Permanent or timing? Will this reverse next period?
- Management action: What is being done
- Forecast impact: Does this change full-year outlook?
3. Top 3 Variances Requiring Attention
Ranked by materiality and strategic significance.
4. Forecast Revision
Does the full-year forecast need updating? State revised expectation and key assumptions.
5. Executive Summary
3-4 sentences of management commentary suitable for a board pack.
Quality Checks
- All variances above threshold explained
- Root causes specific (not vague)
- Favourable/Adverse correctly labelled
- Forecast impact stated for material variances
Anti-Patterns
- Do not explain a variance as "timing" without specifying which period it will reverse into and what amount is expected
- Do not label a favourable variance on a cost line without checking whether it is due to underspend, delayed spend, or reduced activity — the cause determines whether it is genuinely good news
- Do not omit variances below the materiality threshold entirely — note them collectively so the reader knows they exist and were reviewed
- Do not present a variance analysis without a forecast impact statement for material items — historical variances without forward implications are incomplete
Example Trigger Phrases
- "Write a variance analysis for these actuals vs budget: [paste]"
- "Explain why we are over budget on [cost line]"
- "Write the variance commentary for our finance review"
- "Produce a budget vs actual analysis for Q[N]"