Case Study Absorption Vs Marginal Costing And Decision-Making

Marginal Costing and Absorption Costing

Learning Objectives

  • To understand the meanings of marginal cost and marginal costing
  • To distinguish between marginal costing and absorption costing
  • To ascertain income under both marginal costing and absorption costing

IntroductionThe costs that vary with a decision should only be included in decision analysis. For many decisions that involve relatively small variations from existing practice and/or are for relatively limited periods of time, fixed costs are not relevant to the decision. This is because either fixed costs tend to be impossible to alter in the short term or managers are reluctant to alter them in the short term.

Marginal costing - definition

Marginal costing distinguishes between fixed costs and variable costs as convention ally classified.

The marginal cost of a product –“ is its variable cost”. This is normally taken to be; direct labour, direct material, direct expenses and the variable part of overheads.

Marginal costing is formally defined as:

‘the accounting system in which variable costs are charged to cost units and the fixed costs of the period are written-off in full against the aggregate contribution. Its special value is in decision making’. (Terminology.)

The term ‘contribution’ mentioned in the formal definition is the term given to the difference between Sales and Marginal cost. Thus










The term marginal cost sometimes refers to the marginal cost per unit and sometimes to the total marginal costs of a department or batch or operation. The meaning is usually clear from the context.


Alternative names for marginal costing are the contribution approach and direct costing In this lesson, we will study marginal costing as a technique quite distinct from absorption costing.

Theory of Marginal Costing

The theory of marginal costing as set out in “A report on Marginal Costing” published by CIMA, London is as follows:

In relation to a given volume of output, additional output can normally be obtained at less than proportionate cost because within limits, the aggregate of certain items of cost will tend to remain fixed and only the aggregate of the remainder will tend to rise proportionately with an increase in output. Conversely, a decrease in the volume of output will normally be accompanied by less than proportionate fall in the aggregate cost.

The theory of marginal costing may, therefore, by understood in the following two steps:

1.     If the volume of output increases, the cost per unit in normal circumstances reduces. Conversely, if an output reduces, the cost per unit increases. If a factory produces 1000 units at a total cost of $3,000 and if by increasing the output by one unit the cost goes up to $3,002, the marginal cost of additional output will be $.2.

2.     If an increase in output is more than one, the total increase in cost divided by the total increase in output will give the average marginal cost per unit. If, for example, the output is increased to 1020 units from 1000 units and the total cost to produce these units is $1,045, the average marginal cost per unit is $2.25. It can be described as follows:

Additional cost =

Additional units

$ 45 = $2.25


The ascertainment of marginal cost is based on the classification and segregation of cost into fixed and variable cost. In order to understand the marginal costing technique, it is essential to understand the meaning of marginal cost.

Marginal cost means the cost of the marginal or last unit produced. It is also defined as the cost of one more or one less unit produced besides existing level of production. In this connection, a unit may mean a single commodity, a dozen, a gross or any other measure of goods.

For example, if a manufacturing firm produces X unit at a cost of $ 300 and X+1 units at a cost of $ 320, the cost of an additional unit will be $ 20 which is marginal cost. Similarly if the production of X-1 units comes down to $ 280, the cost of marginal unit will be $ 20 (300–280).

The marginal cost varies directly with the volume of production and marginal cost per unit remains the same. It consists of prime cost, i.e. cost of direct materials, direct labor and all variable overheads. It does not contain any element of fixed cost which is kept separate under marginal cost technique.

Marginal costing may be defined as the technique of presenting cost data wherein variable costs and fixed costs are shown separately for managerial decision-making. It should be clearly understood that marginal costing is not a method of costing like process costing or job costing. Rather it is simply a method or technique of the analysis of cost information for the guidance of management which tries to find out an effect on profit due to changes in the volume of output.

There are different phrases being used for this technique of costing. In UK, marginal costing is a popular phrase whereas in US, it is known as direct costing and is used in place of marginal costing. Variable costing is another name of marginal costing.

Marginal costing technique has given birth to a very useful concept of contribution where contribution is given by: Sales revenue less variable cost (marginal cost)

Contribution may be defined as the profit before the recovery of fixed costs. Thus, contribution goes toward the recovery of fixed cost and profit, and is equal to fixed cost plus profit (C = F + P).

In case a firm neither makes profit nor suffers loss, contribution will be just equal to fixed cost (C = F). this is known as break even point.

The concept of contribution is very useful in marginal costing. It has a fixed relation with sales. The proportion of contribution to sales is known as P/V ratio which remains the same under given conditions of production and sales.

The principles of marginal costing

The principles of marginal costing are as follows.

a.      For any given period of time, fixed costs will be the same, for any volume of sales and production (provided that the level of activity is within the ‘relevant range’). Therefore, by selling an extra item of product or service the following will happen.

§  Revenue will increase by the sales value of the item sold.

§  Costs will increase by the variable cost per unit.

§  Profit will increase by the amount of contribution earned from the extra item.

b.     Similarly, if the volume of sales falls by one item, the profit will fall by the amount of contribution earned from the item.

c.      Profit measurement should therefore be based on an analysis of total contribution. Since fixed costs relate to a period of time, and do not change with increases or decreases in sales volume, it is misleading to charge units of sale with a share of fixed costs.

d.     When a unit of product is made, the extra costs incurred in its manufacture are the variable production costs. Fixed costs are unaffected, and no extra fixed costs are incurred when output is increased.

Features of Marginal CostingThe main features of marginal costing are as follows:

1.     Cost Classification
The marginal costing technique makes a sharp distinction between variable costs and fixed costs. It is the variable cost on the basis of which production and sales policies are designed by a firm following the marginal costing technique.

2.     Stock/Inventory Valuation
Under marginal costing, inventory/stock for profit measurement is valued at marginal cost. It is in sharp contrast to the total unit cost under absorption costing method.

3.     Marginal Contribution
Marginal costing technique makes use of marginal contribution for marking various decisions. Marginal contribution is the difference between sales and marginal cost. It forms the basis for judging the profitability of different products or departments.

Advantages and Disadvantages of Marginal Costing TechniqueAdvantages

1.     Marginal costing is simple to understand.

2.     By not charging fixed overhead to cost of production, the effect of varying charges per unit is avoided.

3.     It prevents the illogical carry forward in stock valuation of some proportion of current year’s fixed overhead.

4.     The effects of alternative sales or production policies can be more readily available and assessed, and decisions taken would yield the maximum return to business.

5.     It eliminates large balances left in overhead control accounts which indicate the difficulty of ascertaining an accurate overhead recovery rate.

6.     Practical cost control is greatly facilitated. By avoiding arbitrary allocation of fixed overhead, efforts can be concentrated on maintaining a uniform and consistent marginal cost. It is useful to various levels of management.

7.     It helps in short-term profit planning by breakeven and profitability analysis, both in terms of quantity and graphs. Comparative profitability and performance between two or more products and divisions can easily be assessed and brought to the notice of management for decision making.


1.     The separation of costs into fixed and variable is difficult and sometimes gives misleading results.

2.     Normal costing systems also apply overhead under normal operating volume and this shows that no advantage is gained by marginal costing.

3.     Under marginal costing, stocks and work in progress are understated. The exclusion of fixed costs from inventories affect profit, and true and fair view of financial affairs of an organization may not be clearly transparent.

4.     Volume variance in standard costing also discloses the effect of fluctuating output on fixed overhead. Marginal cost data becomes unrealistic in case of highly fluctuating levels of production, e.g., in case of seasonal factories.

5.     Application of fixed overhead depends on estimates and not on the actuals and as such there may be under or over absorption of the same.

6.     Control affected by means of budgetary control is also accepted by many. In order to know the net profit, we should not be satisfied with contribution and hence, fixed overhead is also a valuable item. A system which ignores fixed costs is less effective since a major portion of fixed cost is not taken care of under marginal costing.

7.     In practice, sales price, fixed cost and variable cost per unit may vary. Thus, the assumptions underlying the theory of marginal costing sometimes becomes unrealistic. For long term profit planning, absorption costing is the only answer.

Presentation of Cost Data under Marginal Costing and Absorption CostingMarginal costing is not a method of costing but a technique of presentation of sales and cost data with a view to guide management in decision-making.

The traditional technique popularly known as total cost or absorption costing technique does not make any difference between variable and fixed cost in the calculation of profits. But marginal cost statement very clearly indicates this difference in arriving at the net operational results of a firm.

Following presentation of two Performa shows the difference between the presentation of information according to absorption and marginal costing techniques:




Sales Revenue


Less Marginal Cost of Sales

Opening Stock (Valued @ marginal cost)


Add Production Cost (Valued @ marginal cost)


Total Production Cost


Less Closing Stock (Valued @ marginal cost)


Marginal Cost of Production


Add Selling, Admin & Distribution Cost


Marginal Cost of Sales




Less Fixed Cost


Marginal Costing Profit





Sales Revenue


Less Absorption Cost of Sales

Opening Stock (Valued @ absorption cost)


Add Production Cost (Valued @ absorption cost)


Total Production Cost


Less Closing Stock (Valued @ absorption cost)


Absorption Cost of Production


Add Selling, Admin & Distribution Cost


Absorption Cost of Sales


Un-Adjusted Profit


Fixed Production O/H absorbed


Fixed Production O/H incurred


(Under)/Over Absorption


Adjusted Profit


Reconciliation Statement for Marginal Costing and Absorption Costing Profit


Marginal Costing Profit



(Closing stock – opening Stock) x OAR


= Absorption Costing Profit


Where OAR( overhead absorption rate) =

Budgeted fixed production overhead

Budgeted levels of activities

Marginal Costing versus Absorption Costing

After knowing the two techniques of marginal costing and absorption costing, we have seen that the net profits are not the same because of the following reasons:1. Over and Under Absorbed Overheads

In absorption costing, fixed overheads can never be absorbed exactly because of difficulty in forecasting costs and volume of output. If these balances of under or over absorbed/recovery are not written off to costing profit and loss account, the actual amount incurred is not shown in it. In marginal costing, however, the actual fixed overhead incurred is wholly charged against contribution and hence, there will be some difference in net profits.

2. Difference in Stock Valuation

In marginal costing, work in progress and finished stocks are valued at marginal cost, but in absorption costing, they are valued at total production cost. Hence, profit will differ as different amounts of fixed overheads are considered in two accounts.

The profit difference due to difference in stock valuation is summarized as follows:

a.      When there is no opening and closing stocks, there will be no difference in profit.

b.     When opening and closing stocks are same, there will be no difference in profit, provided the fixed cost element in opening and closing stocks are of the same amount.

c.      When closing stock is more than opening stock, the profit under absorption costing will be higher as comparatively a greater portion of fixed cost is included in closing stock and carried over to next period.

d.     When closing stock is less than opening stock, the profit under absorption costing will be less as comparatively a higher amount of fixed cost contained in opening stock is debited during the current period.

The features which distinguish marginal costing from absorption costing are as follows.

a.      In absorption costing, items of stock are costed to include a ‘fair share’ of fixed production overhead, whereas in marginal costing, stocks are valued at variable production cost only. The value of closing stock will be higher in absorption costing than in marginal costing.

b.     As a consequence of carrying forward an element of fixed production overheads in closing stock values, the cost of sales used to determine profit in absorption costing will:

                               i.            include some fixed production overhead costs incurred in a previous period but carried forward into opening stock values of the current period;

                             ii.            exclude some fixed production overhead costs incurred in the current period by including them in closing stock values.

In contrast marginal costing charges the actual fixed costs of a period in full into the profit and loss account of the period. (Marginal costing is therefore sometimes known as period costing.)

c.      In absorption costing, ‘actual’ fully absorbed unit costs are reduced by producing in greater quantities, whereas in marginal costing, unit variable costs are unaffected by the volume of production (that is, provided that variable costs per unit remain unaltered at the changed level of production activity). Profit per unit in any period can be affected by the actual volume of production in absorption costing; this is not the case in marginal costing.

d.     In marginal costing, the identification of variable costs and of contribution enables management to use cost information more easily for decision-making purposes (such as in budget decision making). It is easy to decide by how much contribution (and therefore profit) will be affected by changes in sales volume. (Profit would be unaffected by changes in production volume).In absorption costing, however, the effect on profit in a period of changes in both:

                               i.            production volume; and

                             ii.            sales volume;
is not easily seen, because behaviour is not analysed and incremental costs are not used in the calculation of actual profit.

Limitations of Absorption CostingThe following are the criticisms against absorption costing:

1.     You might have observed that in absorption costing, a portion of fixed cost is carried over to the subsequent accounting period as part of closing stock. This is an unsound practice because costs pertaining to a period should not be allowed to be vitiated by the inclusion of costs pertaining to the previous period and vice versa.

2.     Further, absorption costing is dependent on the levels of output which may vary from period to period, and consequently cost per unit changes due to the existence of fixed overhead. Unless fixed overhead rate is based on normal capacity, such changed costs are not helpful for the purposes of comparison and control.

The cost to produce an extra unit is variable production cost. It is realistic to the value of closing stock items as this is a directly attributable cost. The size of total contribution varies directly with sales volume at a constant rate per unit. For the decision-making purpose of management, better information about expected profit is obtained from the use of variable costs and contribution approach in the accounting system.Summary

Marginal cost is the cost management technique for the analysis of cost and revenue information and for the guidance of management. The presentation of information through marginal costing statement is easily understood by all mangers, even those who do not have preliminary knowledge and implications of the subjects of cost and management accounting.

Absorption costing and marginal costing are two different techniques of cost accounting. Absorption costing is widely used for cost control purpose whereas marginal costing is used for managerial decision-making and control.


Chapter 3 – Breakeven Analysis

Learning Objectives

  • To describe as to how the concepts of fixed and variable costs are used in C-V-P analysis
  • To segregate semi-variable expenses in C-V-P analysis
  • To identify the limiting assumptions of C-V-P analysis
  • To work out the breakeven analysis, contribution analysis and margin of safety
  • To understand how to draw a breakeven chart
  • To compute breakeven point

IntroductionIn this lesson, we will discuss in detail the highlights associated with cost function and cost relations with the production and distribution system of an economic entity.

To assist planning and decision making, management should know not only the budgeted profit, but also:

  • the output and sales level at which there would neither profit nor loss (break-even point)
  • the amount by which actual sales can fall below the budgeted sales level, without a loss being incurred (the margin of safety)

MARGINAL COSTS, CONTRIBUTION AND PROFITA marginal cost is another term for a variable cost. The term ‘marginal cost’ is usually applied to the variable cost of a unit of product or service, whereas the term ‘variable cost’ is more commonly applied to resource costs, such as the cost of materials and labour hours.

Marginal costing is a form of management accounting based on the distinction between:

a.      the marginal costs of making selling goods or services, and

b.     fixed costs, which should be the same for a given period of time, regardless of the level of activity in the period.

Suppose that a firm makes and sells a single product that has a marginal cost of £5 per unit and that sells for £9 per unit. For every additional unit of the product that is made and sold, the firm will incur an extra cost of £5 and receive income of £9. The net gain will be £4 per additional unit. This net gain per unit, the difference between the sales price per unit and the marginal cost per unit, is called contribution.

Contribution is a term meaning ‘making a contribution towards covering fixed costs and making a profit’. Before a firm can make a profit in any period, it must first of all cover its fixed costs. Breakeven is where total sales revenue for a period just covers fixed costs, leaving neither profit nor loss. For every unit sold in excess of the breakeven point, profit will increase by the amount of the contribution per unit.

C-V-P analysis is broadly known as cost-volume-profit analysis. Specifically speaking, we all are concerned with in-depth analysis and application of CVP in practical world of industry management.

Cost-Volume-Profit (C-V-P) Relationship

We have observed that in marginal costing, marginal cost varies directly with the volume of production or output. On the other hand, fixed cost remains unaltered regardless of the volume of output within the scale of production already fixed by management. In case if cost behavior is related to sales income, it shows cost-volume-profit relationship. In net effect, if volume is changed, variable cost varies as per the change in volume. In this case, selling price remains fixed, fixed remains fixed and then there is a change in profit.

Being a manager, you constantly strive to relate these elements in order to achieve the maximum profit. Apart from profit projection, the concept of Cost-Volume-Profit (CVP) is relevant to virtually all decision-making areas, particularly in the short run.

The relationship among cost, revenue and profit at different levels may be expressed in graphs such as breakeven charts, profit volume graphs, or in various statement forms.

Profit depends on a large number of factors, most important of which are the cost of manufacturing and the volume of sales. Both these factors are interdependent. Volume of sales depends upon the volume of production and market forces which in turn is related to costs. Management has no control over market. In order to achieve certain level of profitability, it has to exercise control and management of costs, mainly variable cost. This is because fixed cost is a non-controllable cost. But then, cost is based on the following factors:

  • Volume of production
  • Product mix
  • Internal efficiency and the productivity of the factors of production
  • Methods of production and technology
  • Size of batches
  • Size of plant

Thus, one can say that cost-volume-profit analysis furnishes the complete picture of the profit structure. This enables management to distinguish among the effect of sales, fluctuations in volume and the results of changes in price of product/services.In other words, CVP is a management accounting tool that expresses relationship among sale volume, cost and profit. CVP can be used in the form of a graph or an equation. Cost-volume- profit analysis can answer a number of analytical questions. Some of the questions are as follows:

1.     What is the breakeven revenue of an organization?

2.     How much revenue does an organization need to achieve a budgeted profit?

3.     What level of price change affects the achievement of budgeted profit?

4.     What is the effect of cost changes on the profitability of an operation?

Cost-volume-profit analysis can also answer many other “what if” type of questions. Cost-volume-profit analysis is one of the important techniques of cost and management accounting. Although it is a simple yet a powerful tool for planning of profits and therefore, of commercial operations. It provides an answer to “what if” theme by telling the volume required to produce.Following are the three approaches to a CVP analysis:

  • Cost and revenue equations
  • Contribution margin
  • Profit graph

Objectives of Cost-Volume-Profit Analysis

1.     In order to forecast profits accurately, it is essential to ascertain the relationship between cost and profit on one hand and volume on the other.

2.     Cost-volume-profit analysis is helpful in setting up flexible budget which indicates cost at various levels of activities.

3.     Cost-volume-profit analysis assist in evaluating performance for the purpose of control.

If your small business is a manufacturing company, you have the choice of using absorption costing or variable costing in determining your profits. You must learn the implications of each before making this choice. While either method of accounting for costs is valid under generally accepted accounting principles, the method you choose can affect your profit-reporting.

Fixed Overhead Costs

You must understand fixed overhead expenses in order to understand absorption costing and variable costing. Fixed overhead consists of expenses that do not change with your level of production. Examples of fixed overhead include rent, insurance, wages for permanent full-time employees, and lease payments on equipment. These expenses continue no matter what your level of sales or how much you manufacture.

Absorption Costing

Absorption costing is a method whereby you apply part of your fixed overhead costs to the cost of manufacturing products. You do this on a per-unit basis. Simply divide your fixed costs by the number of units you manufactured and sold during the period. The result is a cost per unit for each unit you made and sold.

Variable Costing

Variable costing uses fixed overhead as a lump sum, rather than a per-unit, expense. Under this method, you include all your variable costs such as supplies, raw materials and shipping. You add the full cost of fixed overhead for the period. You do not figure these expenses on a per-unit basis. Instead you subtract them from your revenue figure as a lump-sum expense.

Advantages of Absorption Costing

Absorption costing offers an advantage when you do not sell all of your manufactured products during the accounting period. You may have finished goods in inventory. Because you assign a per-unit amount for fixed expenses, each product in inventory has a value that includes part of the fixed overhead. You do not show the expense until you actually sell the items in inventory. This can improve your profits for the period.

Disadvantages of Absorption Costing

Absorption costing can artificially inflate your profit figures in any given accounting period. Because you will not deduct all of your fixed overhead if you haven't sold all of your manufactured products, your profit-and-loss statement does not show the full expenses you had for the period. This can mislead you when you are analyzing your profitability.

Advantages of Variable Costing

Variable costing shows your profits after all the bills have been paid for the accounting period. Though you may not have received revenues for the products you manufactured because some could be in inventory, you show that you have paid all of your expenses for the period. When you finally sell the finished products in inventory, you have surplus income.

Disadvantages of Variable Costing

Variable costing shows full payment for fixed-overhead expenses for the accounting period. Even if you don’t sell all the products you make, you must deduct the full cost of fixed overhead. This means you show less profit for the period because you show your complete overhead expense even when you haven’t sold all of your products. You show reduced income because of unsold products but full expenses for overhead.

About the Author

Kevin Johnston writes for Ameriprise Financial, the Rutgers University MBA Program and Evan Carmichael. He has written about business, marketing, finance, sales and investing for publications such as "The New York Daily News," "Business Age" and "Nation's Business." He is an instructional designer with credits for companies such as ADP, Standard and Poor's and Bank of America.

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