Flexible Budgets, Budgetary Control and Basic Variances

Learning objectives

By the end of this chapter, you should be able to:

• Prepare a flexible budget at the actual activity level to enable a fair comparison with actual results.
• Calculate and interpret basic variances for revenue and costs, identifying where performance has deviated from expectation.
• Distinguish between control variances (actual vs flexed) and volume effects (actual vs original plan).
• Explain, at a high level, how planning and operational variances can separate changed conditions from execution performance, where a credible revised benchmark exists.
• Produce a short budgetary control report that highlights significant variances and sets out practical management actions.
• Prioritise investigation using significance, recurrence, controllability, and links between variances.

Overview & key concepts

Budgets serve two connected purposes: (1) planning (setting targets and allocating resources) and (2) control (monitoring results and prompting corrective action). A key challenge arises when actual activity differs from the level assumed in the original budget. If output or sales volume changes, a fixed (static) budget becomes an unfair benchmark because it was built for a different activity level.

A flexible budget addresses this by restating budgeted revenue and costs for the actual activity level. Variance analysis then compares:

• Actual results
• The flexed budget (the budget allowed for the actual volume)

This approach highlights where performance differs due to price/rate changes, cost control, or inefficiency—rather than being distorted by volume differences.

Flexible budget

A flexible budget is a budget recalculated for the actual level of activity, using the original budget’s assumptions about cost behaviour.

• Variable items are restated using the budgeted variable rate per unit (or per hour, per service, etc.).
• Fixed items are normally unchanged within the relevant range (unless they are step-fixed or capacity has shifted).
• Mixed (semi-variable) items must be split into fixed and variable components before flexing.

A flexible budget is not a new plan. It is the original plan expressed at the volume that actually occurred, to support fair performance evaluation.

Variance analysis

A variance is the difference between an actual result and a benchmark.

Two benchmarks matter:

• Theflexed budget: used for control (what costs and revenue should have been at the actual activity level).
• Theoriginal fixed budget: still relevant for planning, target-setting, and analysing volume effects (for example, sales volume variance).

In control analysis, the main benchmark is the flexed budget because it reflects the activity actually achieved. The original budget remains important for planning discipline and for understanding how much of the outcome was driven purely by volume.

Core theory and frameworks

Flexing the budget

Flexing requires three steps:

1. Select the activity driver (for example, units sold, labour hours, machine hours, service calls).
2. Classify items by behaviour (variable, fixed, mixed).
3. Restate budget figures at actual activity.

For revenue (using the budget selling price):

Flexed revenue = Budget selling price per unit × Actual units

For a purely variable cost:

Flexed variable cost = Budget variable rate per unit × Actual units

Fixed costs are usually held constant in the flexed budget, provided activity remains within the relevant range.

Control variances (actual vs flexed)

A control variance compares actual results with the flexed budget.

Control variance = Actual result − Flexed budget result

Interpretation:

• Revenue: a positive variance is usually favourable.
• Costs: a positive variance is usually adverse (overspend).

Sales price variance

Sales price variance measures the effect of selling at a different price from the budget price, using actual volume.

Sales price variance = (Actual price − Budget price) × Actual quantity

• Actual price higher than budget: favourable.
• Actual price lower than budget: adverse.

Sales volume variance (contribution basis)

Sales volume variance measures the effect on contribution of selling a different volume from the original plan, valued at the budget contribution per unit. It is a volume effect, not a control variance.

Sales volume variance (contribution basis) = (Actual quantity − Budget quantity) × Budget contribution per unit

In this chapter, sales volume variance is measured on a contribution basis for internal management control purposes.

Total variable cost control variance

Where only a budgeted variable cost per unit is available (with no separate input quantity and rate standards), the most direct analysis is the total variable cost control variance, comparing actual total variable cost with the flexed variable cost allowed for the achieved activity.

Total variable cost control variance = Actual total variable cost − Flexed variable cost

This shows whether variable costs in total were above or below the amount expected for the activity achieved. If detailed standards exist (for example, standard input quantity per unit and a standard rate), the variance can be analysed further into rate/price and efficiency/usage elements.

Fixed cost spending variance

In basic flexible budgeting, fixed costs are normally unchanged in the flexed budget (within the relevant range). The variance is therefore commonly expressed against the budgeted fixed cost.

Fixed cost spending variance = Actual fixed costs − Budgeted fixed costs

A positive figure indicates overspending (adverse).

Efficiency variance as a standard costing concept

Efficiency variances require standard costing information:

• a standard input allowance for the achieved output (for example, standard labour hours per unit), and
• separation of input quantity from input rate (for example, hours and £ per hour).

A common labour format is:

Labour efficiency variance = (Actual hours − Standard hours for actual output) × Standard rate per hour

If you do not have a standard input allowance and a standard rate, do not force an efficiency calculation. In that case, use the total variable cost control variance and investigate the underlying cost drivers using operational information (waste, overtime, supplier changes, yield, etc.).

Planning vs operational variances

In some situations, management may revise expectations during the period because conditions change (for example, market price movements or supplier price changes). Planning and operational variances can separate:

• the effect of changed conditions (planning), and
• the effect of execution against revised expectations (operational)

This split is only useful if the revised benchmark is credible and supportable using evidence available during the period. Without that discipline, the split becomes subjective and can drift into hindsight adjustment.

A simple sales price illustration:

• Budget price: £20
• Revised expected price (supported by market evidence): £18
• Actual price achieved: £17

Planning element:

Planning price variance = (Revised price − Budget price) × Actual quantity

Operational element:

Operational price variance = (Actual price − Revised price) × Actual quantity

Worked example

Narrative scenario

ABC Ltd produces a single product (widgets). The budget for the period was based on producing and selling 8,000 units at a selling price of £25 per unit. Budgeted variable cost is £14 per unit and budgeted fixed costs are £72,000 per period.

Actual sales volume for the period was 9,200 units.

Actual results:

• Revenue: £226,320
• Variable costs: £132,480
• Fixed costs: £74,100

Required

1. Prepare a flexible budget for 9,200 units.
2. Calculate the sales price variance.
3. Calculate the total variable cost control variance.
4. Calculate the fixed cost spending variance.
5. Interpret the results and provide recommendations.

Solution

Step 1: Fixed budget (8,000 units)

Budget revenue = 8,000 × £25 = £200,000
Budget variable cost = 8,000 × £14 = £112,000
Budget contribution = £88,000
Budget fixed costs = £72,000
Budget profit = £16,000

Step 2: Flexible budget (9,200 units)

Flexed revenue = 9,200 × £25 = £230,000
Flexed variable cost = 9,200 × £14 = £128,800
Flexed contribution = £101,200
Flexed fixed costs = £72,000
Flexed profit = £29,200

Step 3: Actual profit and overall profit control variance

Actual profit:

Actual profit = £226,320 − £132,480 − £74,100 = £19,740

Profit variance versus flexed budget:

Profit control variance = Actual profit − Flexed profit
Profit control variance = £19,740 − £29,200 = −£9,460 (Adverse)

Step 4: Sales price variance

Actual selling price per unit:

Actual price = £226,320 / 9,200 = £24.60 per unit

Sales price variance = (Actual price − Budget price) × Actual quantity
Sales price variance = (£24.60 − £25.00) × 9,200
Sales price variance = (−£0.40) × 9,200 = −£3,680 (Adverse)

Step 5: Total variable cost control variance

Flexed variable cost (allowed at 9,200 units) = £128,800
Actual variable cost = £132,480

Total variable cost control variance = Actual variable cost − Flexed variable cost
Total variable cost control variance = £132,480 − £128,800 = £3,680 (Adverse)

Supporting insight (useful for interpretation):
Actual variable cost per unit = £132,480 / 9,200 = £14.40 per unit
Budget variable cost per unit = £14.00 per unit
Difference = £0.40 adverse per unit

This variance cannot be split into rate/price and efficiency/usage without additional standard costing detail (for example, standard material quantity per unit and a standard material price).

Step 6: Fixed cost spending variance

Budgeted fixed costs = £72,000
Actual fixed costs = £74,100

Fixed cost spending variance = Actual fixed costs − Budgeted fixed costs
Fixed cost spending variance = £74,100 − £72,000 = £2,100 (Adverse)

Step 7: Reconciliation check

Profit control variance (adverse) should be explained by movements versus the flexed budget:

• Sales price variance: £3,680 A
• Total variable cost control variance: £3,680 A
• Fixed cost spending variance: £2,100 A

Total adverse = £3,680 + £3,680 + £2,100 = £9,460 A ✔

Interpretation and recommendations

1. Selling price pressure reduced profit.
2. The business sold 9,200 units (higher volume than planned), but the average selling price was £24.60 instead of £25.00. A £0.40 reduction per unit caused a £3,680 adverse sales price variance. Management should confirm whether this reflects deliberate discounting, weaker negotiating power, or competitive pressure, and whether the lower price increased volume enough to protect overall contribution.
3. Variable costs were higher than expected for the activity achieved.
4. Variable costs averaged £14.40 per unit against a £14.00 budget, producing a £3,680 adverse total variable cost control variance. Likely drivers include higher input prices, waste, overtime premiums, lower yields, or unfavourable supplier terms. The variance should be investigated by breaking variable costs into components (materials, labour, variable overhead) and focusing on the largest and most controllable drivers.
5. Fixed costs exceeded the expected level.
6. Fixed costs were £2,100 above budget. Management should review whether the overspend is recurring or one-off and whether it indicates weak cost authorisation, unavoidable cost inflation, or step-cost effects linked to supporting higher activity.
7. Investigation priority should reflect management attention limits.
8. Investigate variances based on size, recurrence, controllability, and interaction with other variances (for example, discounting may link to higher volume; higher variable costs may link to quality issues or overtime caused by capacity pressure).

Budgetary control report (example format)

ABC Ltd — Budgetary control summary (9,200 units)

• Flexed profit: £29,200
• Actual profit: £19,740
• Profit control variance: £9,460 adverse

Key variances to investigate (ranked):

1. Total variable cost control variance: £3,680 A
   • Likely causes: input price increases, waste, overtime, yield loss
   • Actions: analyse variable cost breakdown; review purchasing and process controls; check scrap/rework
2. Sales price variance: £3,680 A
   • Likely causes: discounting, competitor pressure, weaker customer mix
   • Actions: review pricing approvals; analyse margin by customer/channel; reassess pricing and sales incentives
3. Fixed cost spending variance: £2,100 A
   • Likely causes: repairs, utilities, indirect cost creep, step-cost increases
   • Actions: review cost ledger; separate one-off from recurring; tighten authorisation and forecasting

Common pitfalls and misunderstandings

• Comparing actual results to the original budget without flexing.Volume differences then get mislabelled as “performance”.
• Forgetting the original budget still matters.It remains important for planning, target-setting, and analysing volume effects.
• Treating mixed costs as fully fixed or fully variable.Mixed costs must be split before flexing.
• Using inconsistent favourable/adverse conventions.Apply one clear rule throughout.
• Ignoring the relevant range.Fixed costs may be stable only within a capacity band; step-changes can occur.
• Investigating everything.Focus on large, recurring, controllable variances.
• Stopping at the number.A variance is a signal; value comes from identifying cause and deciding action.
• Assuming “favourable” is always good.Underspending on maintenance, training, or quality control can create later costs.
• Mixing flexible budget control with standard costing without signposting.Efficiency variances require standard input allowances and standard rates.

Summary

Flexible budgets restate the original plan at the actual activity level so performance can be assessed fairly. Control variances then show where outcomes differed from what would have been expected at that activity level, helping management focus on selling prices, cost control, and operational discipline. The original budget remains important for planning and for understanding volume effects on contribution.

Planning and operational variances can be a useful extension where revised benchmarks are credible and documented during the period, but they should not be used as a retrospective justification after results are known.

FAQ

What is the main purpose of a flexible budget?

A flexible budget restates budgeted revenue and costs for the activity level actually achieved. This allows a fair comparison with actual results and helps ensure variances reflect performance issues rather than volume differences.

How do you calculate a sales price variance?

Sales price variance = (Actual price − Budget price) × Actual quantity

It isolates the effect of a higher or lower selling price than planned, using actual volume.

What is the difference between control variances and volume effects?

Control variances compare actual results to the flexed budget (performance at the achieved activity level). Volume effects compare actual volume to planned volume (how contribution changes because volume changed), typically using a contribution-based sales volume variance.

Why is “efficiency variance” not always appropriate in basic flexible budgeting?

Efficiency variances require standard costing detail: a standard input allowance for the achieved output and a separate standard rate. If you only have a budgeted variable cost per unit, use a total variable cost control variance instead and investigate operational drivers.

When are planning and operational variances useful?

They are useful when a revised benchmark can be justified using evidence available during the period (for example, observable market price changes). Without a supportable revised benchmark, splitting variances becomes subjective and unhelpful.

How should variances be prioritised for investigation?

Prioritise by size, recurrence, controllability, and the way variances interact (for example, price reductions may drive volume increases; overtime may drive higher variable cost per unit).

Summary (Recap)

This chapter explained how flexible budgets adjust the original plan to the actual activity level, creating a fair basis for control. It set out how to calculate and interpret basic control variances, including sales price variance, total variable cost control variance, and fixed cost spending variance, and showed how to reconcile them to an overall profit control variance. It also clarified how volume effects can be analysed separately using a contribution-based sales volume variance and signposted planning/operational variances as an extension that requires credible revised benchmarks.

Glossary

Flexible budget
A budget recalculated for the actual activity level using the original assumptions about cost behaviour, used to support fair performance evaluation.

Fixed (static) budget
The original budget prepared for a single planned activity level, not adjusted for the activity that actually occurred.

Control variance
The difference between actual results and the flexed budget, used to assess performance at the achieved activity level.

Variance
The difference between an actual result and a benchmark figure, used to identify and investigate causes of deviation.

Favourable variance
A variance that improves profit relative to the benchmark (for example, higher revenue than expected or lower cost than expected).

Adverse variance
A variance that reduces profit relative to the benchmark (for example, lower revenue than expected or higher cost than expected).

Sales price variance
The effect on revenue (or contribution) of the actual selling price differing from the budget price, using actual volume.

Sales volume variance (contribution basis)
The effect on contribution of actual volume differing from budget volume, valued at budget contribution per unit.

Total variable cost control variance
The difference between actual total variable cost and the flexed variable cost allowed for the activity achieved.

Fixed cost spending variance
The difference between actual fixed costs and the budgeted fixed costs.

Planning variance
The part of a variance caused by conditions differing from those assumed when the original budget was set.

Operational variance
The part of a variance caused by actual performance differing from a revised, supportable benchmark.

Relevant range
The activity band within which cost behaviour assumptions (especially fixed cost stability) are expected to hold.

Responsibility centre
A unit or function where a manager is accountable for costs, revenue, or profit within their area of control.

Controllable cost
A cost a manager can influence within the relevant time frame through decisions and actions.