Cost centres and cost units explain where costs are collected and how output is measured. One helps organise the records. The other helps express a cost in a meaningful form.
Cost centres and cost units: use a simple printing example
A printing business may collect costs separately for its printing department, finishing department and administration department. These can serve as cost centres. To measure the cost of production, it might use a finished brochure as a cost unit.
The printing department is not the brochure. It is an organisational area that incurs costs. A brochure is a unit of output. Keeping those ideas separate helps when you later work with allocation and apportionment.
| Business | Possible cost centre | Possible cost unit |
|---|---|---|
| Print shop | Finishing department | Finished brochure |
| Delivery service | Dispatch function | Completed delivery |
| Clinic | Consultation department | Consultation of a defined type |
These are illustrations, not universal definitions. A delivery across town is not necessarily comparable with a long-distance delivery. A business needs consistent definitions if it wants useful comparisons.
Choose a unit that reflects the work
Suppose a transport business reports only “cost per journey”, but some journeys are ten times longer than others. The average may be arithmetically correct and still be unhelpful. Distance, capacity and the service provided may need to be considered.
For a beginner’s exercise, identify what is being produced before calculating a unit cost. Do not divide total costs by a convenient number just because the question contains it. State the output measure and the time period.
Collect costs before sharing them
A finishing supervisor’s salary may be directly attributable to the finishing department. Shared building rent may need to be apportioned between departments using a reasonable basis, such as floor area, if the facts support that basis.
Allocating a cost to a department and calculating the cost per brochure are separate steps. A sound answer explains both the collection of costs and the output to which those costs relate.
Try the classification
A repair business tracks costs for its workshop and charges customers for standard services. Which could be a cost centre and which could be a cost unit?
Answer: the workshop can be a cost centre. A clearly defined standard service can be a cost unit. If repairs differ widely in complexity, the business may need a more detailed measure, such as a specific repair type or labour hour, rather than treating every repair as identical.
Check definitions before comparing performance
If one department reports cost per completed unit and another reports cost per unit started, their figures are not directly comparable. Consistent definitions are part of good management information.
Build these foundations through the MA1 course and use the official MA1 study guide to organise your revision.
Work through cost collection with numbers
Assume a small factory has a machining department and a finishing department. Monthly salaries directly attributable to machining are PKR 120,000 and salaries attributable to finishing are PKR 80,000. Shared building rent is PKR 60,000. Machining occupies 60% of the relevant floor area and finishing occupies 40%. For this illustration, floor area is an appropriate basis for sharing rent.
Allocate the salaries to their respective departments because each amount can be traced to one centre. Apportion rent as PKR 36,000 to machining and PKR 24,000 to finishing. Before considering other costs, machining has PKR 156,000 and finishing has PKR 104,000. Together they total PKR 260,000, matching the salaries of PKR 200,000 plus rent of PKR 60,000. This total check catches a cost that has been lost or counted twice.
If all 10,000 finished units use both departments and the exercise assumes identical units with no work in progress, these particular costs average PKR 26 per finished unit. That is not necessarily the complete product cost: materials, other overheads and any required adjustments would still need consideration. Explain the scope of the numerator before presenting a unit cost as a full cost figure.
Allocation and apportionment are different
Allocation assigns a whole cost to a centre when it belongs there. Apportionment divides a shared cost between centres using a suitable basis. A department’s dedicated equipment rental can be allocated to that department. A shared security cost may need to be apportioned. The choice of basis should reflect the benefit received or another reasonable relationship supported by the facts.
Floor area may suit building occupancy costs but may be weak for a cost driven by machine usage. Employee numbers might suit some staff facilities, while machine hours may better represent certain operating costs. Do not choose a basis solely because its numbers are easiest to use. In an exam, use the prescribed basis and show the calculation clearly.
Production and service cost centres
A production centre performs work directly involved in making the output. A service centre supports other centres, such as maintenance or an internal stores function. Its costs may be collected separately and then shared with the centres receiving its services. The service centre’s existence does not mean its costs disappear from the organisation’s total.
For example, a maintenance team serves machining and finishing. If the question states that maintenance hours are the basis, allocate the support cost according to those hours. Keep the initial collection separate from the subsequent sharing. More advanced questions may describe interactions between service centres, but the basic purpose remains to trace the flow of costs transparently.
Choose a composite unit when one measure is insufficient
Transport often illustrates why a composite cost unit can help. A passenger-kilometre combines the number of passengers with the distance travelled. Carrying 20 passengers for 30 kilometres represents 600 passenger-kilometres. A simple cost per journey would not distinguish this service from carrying five passengers for ten kilometres.
A hotel might consider occupied room-nights, while another business might measure tonne-kilometres for freight. These measures are useful only when their definitions and cost scope are consistent. For example, a room-night figure may be affected by room type and included services. A composite unit improves the description of activity but does not automatically make every service comparable.
Compare a budget and actual cost carefully
Suppose a department budgeted PKR 100,000 to produce 5,000 comparable units but actually spent PKR 108,000 to produce 6,000. Budget cost per unit is PKR 20, while actual cost per unit is PKR 18. Looking only at total spending suggests an increase; looking only at unit cost suggests improvement. Neither observation fully explains performance without considering activity and cost behaviour.
Higher output can spread fixed costs more widely, even if no operational efficiency has improved. Review variable costs, quality, rework and service levels before drawing a conclusion. The cost centre identifies where the cost is reported, and the cost unit helps relate it to activity. Interpretation still requires the circumstances behind both figures.
Responsibility should reflect controllability
A department manager may influence staff scheduling or material waste while having little control over centrally negotiated rent. A report can include both kinds of costs, but performance assessment should distinguish what the manager could reasonably affect. A cost centre is a reporting structure; it does not prove that every reported cost is controlled by its local manager.
Revision exercise: design the information first
Choose a familiar business and name two sensible cost centres. Then define one output unit, a reporting period and a shared cost basis. Explain which costs can be allocated directly and which need apportionment. Finally, identify one limitation of the resulting average. This exercise connects the definitions with the practical purpose of management information instead of treating them as separate vocabulary terms.
Frequently asked questions
Is a cost centre always a physical location?
No. It may be a department, function, person or other area used to collect and control costs, depending on the organisation’s reporting system.
Can a service business have cost units?
Yes. A service can use a meaningful unit such as a delivery, consultation or passenger journey, provided the definition suits the activity being measured.