Performance Management · Budgetary systems and types of budget

Fixed, Flexible, Rolling and Continuous Budgets Explained

Updated 11 October 2026 · Fact-checked

A fixed budget is set for one planned activity level and is not changed. A flexible budget is recalculated for the actual activity level, so costs are compared fairly. A rolling (continuous) budget is updated regularly by adding a new period as one ends. Choose the type that suits the purpose: planning or control.

Understand Fixed, Flexible, Rolling and Continuous Budgets

A fixed budget is prepared for one expected level of activity. It is not changed once approved, even if actual activity differs. It is useful for planning and for setting targets, such as cash needs and resource levels. It is poor for control when actual volume differs from budget.

A flexible budget recognises cost behaviour. Variable costs change with activity. Fixed costs stay the same within the relevant range. You recalculate the budget at the actual activity level. This process is called flexing. The result is a like-for-like comparison with actual results.

Why does this matter? Suppose you budget for 1,000 units and make 1,200. Actual variable costs will exceed the fixed budget. That gap looks adverse, but it is just extra volume. Flexing removes this volume effect. What remains are true cost variances, such as price and efficiency.

A rolling budget (also called a continuous budget) is updated at regular intervals. When a period ends, you drop it and add a new period at the end. The budget always covers the same length of time, such as 12 months. You also revise the remaining periods using the latest information. It suits uncertain, fast-changing environments. In ACCA PM, the two terms are treated as meaning the same thing.

Rolling budgets keep managers planning ahead and make budgets more relevant. But they take more time and cost more to prepare. Frequent changes can also cause confusion and budget fatigue. Managers may also lose sight of the targets they are held to.

Key rules to remember

Flexed budget cost (variable): Flexed variable cost = budgeted variable cost per unit × actual activity; Use the actual units produced or sold, not budgeted units.
Flexed budget cost (fixed): Flexed fixed cost = original budgeted fixed cost; Fixed costs do not change within the relevant range.
Semi-variable cost: Total cost = fixed element + (variable rate × activity); Split the cost first, often using the high-low method, then flex only the variable part.
Flexed sales revenue: Flexed revenue = budgeted selling price per unit × actual units sold; Sales revenue is also flexed to actual volume.
Variance against flexed budget: Variance = actual result − flexed budget result; Label it favourable (F) or adverse (A) based on the effect on profit.

How to solve Fixed, Flexible, Rolling and Continuous Budgets questions

Use this method for any question asking you to flex a budget or compare actual with budget.

1Read the question and find the actual activity level (units produced or sold).
2Classify each cost as variable, fixed or semi-variable. Split semi-variable costs into fixed and variable parts.
3Work out the budgeted per-unit figure for each variable item: budget total ÷ budgeted units.
4Multiply each per-unit figure by actual activity. Keep fixed costs at the original budget.
5Total the flexed revenue, costs and profit.
6Compare actual with the flexed budget line by line. Mark each variance F or A by its effect on profit.
7Comment if asked: explain likely causes and why flexing gives a fairer comparison than the fixed budget.

Quickest way: Per-unit flex in three passes

When to use it: Use this in Section A and B objective questions where you only need one or two flexed figures.

Compute the per-unit rate for the needed line only: budget ÷ budget units.
Multiply by actual units, or keep the figure unchanged if it is fixed.
Subtract from the actual figure and decide F or A by profit effect. Check your answer against the options for sign and size.

Common mistakes in Fixed, Flexible, Rolling and Continuous Budgets

Flexing fixed costs along with variable costs.
Students scale every line by the same ratio to save time.
Fix: Tick each line as fixed or variable first. Only variable costs change with activity.
Using budgeted units instead of actual units when flexing.
The budget figures are on the page, so they feel like the right base.
Fix: The flexed budget always uses actual activity. Circle the actual units before you start.
Comparing actual costs with the original fixed budget and calling the gap a cost variance.
Students skip the flexing step.
Fix: Compare actual with the flexed budget. The fixed budget comparison mixes volume and cost effects.
Flexing a semi-variable cost as if it were wholly variable or wholly fixed.
The cost behaviour is hidden in a note.
Fix: Split it into fixed and variable parts first, then flex only the variable part.
Wrongly labelling variances as favourable or adverse.
Students think higher numbers are always good or always bad.
Fix: Higher revenue is F. Higher cost is A. Always judge by the effect on profit.
Presenting rolling budgets as always better, with no disadvantages.
Textbook lists of advantages are easier to remember.
Fix: Give a balanced answer: more relevant and forward-looking, but more costly, time-consuming and possibly unsettling.

Worked examples

Example 1

A company budgets for 5,000 units: sales ₹25,00,000, direct materials ₹7,50,000, direct labour ₹5,00,000 (all variable) and fixed overheads ₹4,00,000. Actual output and sales are 5,600 units: sales ₹27,50,000, materials ₹8,70,000, labour ₹5,80,000, fixed overheads ₹4,10,000. Prepare a flexed budget and calculate the profit variance against it.

Show the solution

Budget per unit: selling price ₹25,00,000 ÷ 5,000 = ₹500. Materials ₹7,50,000 ÷ 5,000 = ₹150. Labour ₹5,00,000 ÷ 5,000 = ₹100.
Flex to 5,600 units: sales 5,600 × ₹500 = ₹28,00,000. Materials 5,600 × ₹150 = ₹8,40,000. Labour 5,600 × ₹100 = ₹5,60,000. Fixed overheads stay ₹4,00,000.
Flexed profit = ₹28,00,000 − ₹8,40,000 − ₹5,60,000 − ₹4,00,000 = ₹10,00,000.
Actual profit = ₹27,50,000 − ₹8,70,000 − ₹5,80,000 − ₹4,10,000 = ₹8,90,000.
Variances: sales ₹50,000 A (27,50,000 vs 28,00,000); materials ₹30,000 A (8,70,000 vs 8,40,000); labour ₹20,000 A (5,80,000 vs 5,60,000); fixed overheads ₹10,000 A.
Total = 50,000 + 30,000 + 20,000 + 10,000 = ₹1,10,000 A. Check: 10,00,000 − 8,90,000 = ₹1,10,000.

Answer: Flexed profit is ₹10,00,000. Actual profit is ₹8,90,000. The profit variance against the flexed budget is ₹1,10,000 adverse.

Example 2

A manager says, 'Our budget is fixed for the year, but demand is volatile and we cannot forecast it beyond three months.' Recommend a budgeting approach and explain its advantages and disadvantages.

Show the solution

Identify the problem: a fixed annual budget becomes out of date when demand changes quickly.
Recommend a rolling budget. Each quarter, drop the quarter just ended, add a new one so the budget always covers a set period, and update remaining quarters with the latest forecasts.
Advantages: plans stay relevant; uncertainty is reduced because near periods are budgeted with better information; managers keep looking ahead; it can reflect changes in the environment.
Disadvantages: more time and cost to prepare; frequent revisions may confuse or demotivate staff; managers may feel targets keep shifting; it needs reliable information systems.
Add flexing: for control within each period, flex the budget to actual activity so that variances are meaningful.

Answer: Recommend a rolling (continuous) budget updated quarterly, with flexing for control. It keeps the budget relevant in uncertain conditions, but costs more time and effort and may unsettle managers.

Exam tips

In Section A and B, work out per-unit figures first. Check whether the question asks for a flexed figure or a variance, and note whether it must be F or A.
In Section C, set out the flexed budget as columns: original budget, flexed budget, actual, variance. Marks go for method and layout, so show every line.
Comment questions often ask why flexing is better than a fixed budget. Say that it removes the effect of volume and isolates cost control performance.
For rolling budgets, give both sides. Link each point to the scenario, such as volatile demand, a new product or high inflation.
Always check how semi-variable costs are described. A cost that is part fixed and part variable must be split before flexing.

Practice questions from Budgetary systems and types of budget

Fixed, Flexible, Rolling and Continuous Budgets in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Fixed, Flexible, Rolling and Continuous Budgets: frequently asked questions

What is the main difference between a fixed and a flexible budget?

A fixed budget stays at the planned activity level whatever happens. A flexible budget is recalculated for the actual activity level. Flexible budgets give a fairer basis for control.

Are rolling budgets and continuous budgets the same in ACCA PM?

Yes. ACCA PM treats them as the same thing. The budget is regularly updated by adding a new period as the current one ends, so it always covers the same length of time.

When should you use a fixed budget?

A fixed budget suits planning, such as setting targets and cash needs, and organisations with stable activity. It also suits fixed-cost-heavy settings. It is less useful for control when activity changes.

How do you prepare a flexible budget in the exam?

Find the budgeted rate per unit for each variable cost and multiply by actual activity. Keep fixed costs at the budgeted amount. Then compare actual results with this flexed budget to find the variances.