ACCT20001 Chap.6 Allocating Support Department Costs
Allocating Support Department Costs
Allocation is rarely a single hop. A firm that wants a full cost for every product runs a cascade: corporate costs reach divisions, support department costs reach operating departments, and the accumulated cost of the operating departments then reaches products. This chapter is about the middle hop, which has a complication worth a method of its own.
Operating departments do the work customers pay for, while support departments such as technology, human resources and maintenance exist to serve the rest of the organisation. Their costs can only reach a product through the operating departments, and the awkward fact is that support departments also serve one another. Three methods handle that.
The direct method ignores support-to-support usage and sends everything straight to the operating departments. The step-down method recognises it in one direction by ranking the support departments, allocating the first one to everything else and then closing it so nothing comes back.
The reciprocal method recognises it in both directions by solving simultaneous equations; the subject asks you to understand it and to compute the other two. None of the three changes the total allocated, which is the first check to run, and the chapter closes with three ways an arithmetically clean allocation stops being defensible.
What this chapter covers
- 01
The allocation cascade, from head office down to products
- 02
Primary and support work-units, and why support cost can only travel through operating departments
- 03
The three methods, and which two the subject asks you to compute
- 04
The direct method: dropping support-to-support usage from the denominator
- 05
The step-down method: ranking, allocating, then closing the department
- 06
Why the second pool includes what the first pushed into it
- 07
Why the total never moves, whichever method is used
- 08
Why the ranking changes the answer, and what justifies a ranking
- 09
Three failures: a driver chosen for convenience, an unjustified sequence, and a department mistaken for an activity
Show why one method gives a higher rate than the other
- 1Under the direct method the support-to-support usage leaves the base, so the denominator is 60,000 plus 20,000, which is 80,000 hours.
- 1The direct rate is therefore $600,000 over 80,000 hours, which is $7.50 an hour.
- 1Under the step-down sequence technology is allocated to every user, so the denominator is the full 100,000 hours.
- 2The step-down rate is $600,000 over 100,000 hours, which is $6.00 an hour, and the $120,000 sent to human resources is added to its pool before that pool is spread.
Key terms
- Operating department
- A department that performs the work customers pay for, such as assembly or finishing, and through which support cost must pass to reach a product.
- Support department
- A department that serves the rest of the organisation rather than the customer, such as technology, human resources or maintenance.
- Direct method
- A method that sends support cost only to the operating departments, as though the support units never served one another.
- Step-down method
- A method that ranks support departments, allocates each in turn to all remaining departments, and closes each once allocated.
- Reciprocal method
- A method that recognises support-to-support usage in both directions by solving simultaneous equations across the support departments.
- Allocation cascade
- The sequence by which corporate cost reaches divisions, support cost reaches operating departments, and operating cost reaches products.
Allocating Support Department Costs FAQ
If the total allocated is the same either way, does the method matter?
It matters to every department and to every product cost built on top of it, which is the whole point. Allocation redistributes rather than creates, so a method that relieves one operating department charges another by the same amount.
The consequences show up later in product costs, in transfer prices and in any performance report built on departmental totals, so the argument is about fairness and causality rather than about the size of the pool.
How should the step-down sequence be decided?
By service rather than by preference. The usual convention is that the department serving the most others goes first, on the reasoning that its cost genuinely flows into the widest set of pools before those pools are spread.
Whatever rule is used, the sequence needs a stated reason: an answer that ranks silently has skipped a judgement the marker is looking for, and reversing the order would give a different split with equal arithmetic validity.
Why is building a cost pool around a department a problem?
Because a department is a place on the organisational chart, not a single kind of work. An engineering pool can contain product design, process design, maintenance, testing and production setup, and those are driven by quite different things. Pooling them and spreading the result on one base mixes drivers together, which is exactly the weakness that activity based costing sets out to fix in the next chapter.
Is the reciprocal method examinable in this subject?
The stated objective asks you to understand all three approaches to spreading support cost while computing only two of them, the direct and the step methods. So be able to describe what the reciprocal method does, which is to recognise support-to-support usage in both directions by solving simultaneous equations, and be ready to say why it is the most faithful of the three, without being expected to solve the equations.
Why does the second pool in a step-down sequence get bigger?
Because it has already received an allocation from the department that went first. If technology is allocated first and sends part of its cost to human resources, the human resources pool that is spread in the second step is its own cost plus the amount just received.
Forgetting to add that transfer in is the most frequent arithmetic error in this topic, and it shows up as a total that no longer equals the sum of the original pools.
Exam move
Set out both methods in the same table shape every time you practise, with the support departments as rows and the operating departments as columns, so that the total column is always visible. Check that total first: if the two methods do not allocate the same amount, something has been double counted and no amount of reasoning will fix it.
Practise stating the sequence rule aloud before you start a step-down question, since the marks attached to justifying the ranking are easier to earn than the arithmetic ones.
Finally, learn the three failures as short named items, because a written question here usually asks you to criticise an allocation rather than to perform one, and a criticism with a name attached reads far better than a general complaint about arbitrariness.
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