Marginal cost

July 27, 2023
In economics and accounting, marginal costing describes the rise or fall in total production costs resulting from a targeted output level change. It changes when more resources are added to make or provide more of a product or service. Managers can improve production and operations, keep tabs on spending in the factory, predict future earnings, and more through the information provided by marginal cost calculations. It considers all costs spent during manufacturing, except for overhead charges. This method is often used in manufacturing because it helps businesses take advantage of economies of scale.

What is marginal cost?

The idea of marginal cost is significant in management accounting because it may assist an organization in maximizing its output via economies of scale. A corporation's earnings may be maximized by producing until the marginal cost (MC) equals the marginal revenue (MR). Because fixed costs remain constant regardless of output volume, increased production results in a lower fixed price per unit as the total is spread over more units. Variable costs vary with production level. Therefore, creating more units will increase variable costs. Organizations must be cautious when growing output involves step costs because of shifts in relevant ranges (for example, new equipment or storage space required).

Comprehending marginal cost

Marginal cost is a business and finance accounting concept that enterprises often use to determine an optimal production level. Manufacturers often consider the expense of incorporating one extra unit into their manufacturing plans.

At a given production level, the advantage of creating one more unit and earning revenue from that commodity reduces the total cost of manufacturing the commodity. The key to decreasing manufacturing expenses is to locate that point or level as soon as feasible.

All expenses that fluctuate with the degree of output are included in the marginal cost. For instance, if a corporation has to construct a new facility to produce more items, the cost is marginal—the sum of marginal cost changes with the quantity produced.

In economics, marginal cost is crucial because a corporation seeking to maximize profits would produce up to the point when the marginal cost (MC) equals marginal revenue. After, the cost of creating an additional item will outweigh the money produced. Data disparities, positive and negative effects, transaction expenses, and pricing discrimination are all economic characteristics that might influence the marginal cost.

Factors influencing the marginal cost

Some resources in the manufacturing process stay fixed irrespective of how many more orders the company gets. These resources have fixed prices that do not fluctuate with the amount produced, resulting in higher productivity. These mostly consist of overhead, administrative, and sales expenditures.

However, the firm may need more resources to increase the manufacturing pace for new orders. Purchasing and sustaining these resources entails variable costs that fluctuate with production volume, raising expenditures. These typically include the price of raw materials and labor. Marginal costing often takes variable costs into account in its computation. It may, however, contain fixed expenditures in circumstances of increased output.

Marginal costing formula

The term "marginal costing" refers to the change in total production costs caused by a change in the required quantity of products or services. Firms use the equations below in financial simulation to optimize cash flow generation:

Marginal cost = Change in total expenses / Change in quantity of units produced

The difference between the production costs at a certain level and the production costs at another is reflected in the change in overall/total expenditures.

The change in unit quantity is the difference in the quantity of products produced at two different levels of manufacturing. Because marginal cost aspires to be following a per-unit assumption, the formula should be employed wherever feasible for a single unit.

The equation above might be utilized when producing more than one extra unit. However, organizations must remember that groupings of manufacturing units may have significantly different marginal cost levels.


Marginal cost = ΔTC / ΔQ ——————————— Equation (I)


·       TC = Total cost

·       Q stands for quantity.

·       Δ = The incremental change of manufacturing one more unit

Depending on the intended output, the overall cost for manufacturing is the total value of variable and fixed costs. Each manufacturing step's variable cost is proportional to the marginal cost. Therefore, let us examine another equation to see how they relate to one another:

TC = FC + (Q x VC) —————————— Equation (II)


·        FC = Fixed cost

·        VC = Variable cost

When we combine equations I and II, we arrive at the following:

MC = ΔTC / ΔQ = VC ————————— Equation (III)

Equation III demonstrates how TC is proportional to VC. It indicates that the overall cost will rise if the variable cost rises, and the reverse is true.

The curve of the marginal cost

The marginal cost curve depicts the connection between the marginal cost and the amount of production generated by this business. The marginal cost curve is often U-shaped, indicating that the marginal cost drops for low production levels and rises for higher output levels. It indicates that when the number of things produced increases, the marginal cost decreases until it achieves a minimal value. After its minimal value is achieved, it begins to rise.

The relevance of marginal costs

Accounting and day-to-day management both benefit from marginal costs. It is a foundation for improving production levels to decrease the cost of goods sold (COGS). As a result, operational expenditures (OPEX) are reduced. When businesses reduce their expenses, they increase their leeway. For instance, they might return debt more rapidly if they have debt. It may minimize their interest expenditure and hence boost their long-term profitability.

Alternatively, companies may decide to lower their products' selling prices to make them more appealing compared to the competitors. If this increases sales volume, their total profitability may remain the same (or improve). Another alternative is to enhance their payouts to business owners. For example, the corporation may provide directors (and staff) incentives and boost dividends to shareholders.

Advantages of marginal costs

The following are some perks of using the marginal cost in cost accounting:

i.       Financial modeling uses the marginal cost formula to maximize cash flow creation.

ii.     Production incremental cost may be determined with its assistance. As a result, the company can monitor expenses without cutting down on production to compensate for inflation.

iii.   It is useful for guiding manufacturing choices. The company may calculate the break-even point when the marginal cost of manufacturing equals the marginal revenue, ensuring maximum profit.

iv.   It aids the manufacturer in resource allocation, allowing for increased output at a manageable cost. The calculation is useful for pinpointing the point at which manufacturing an additional unit of the commodity would result in a loss.

v.     It helps the company decide whether it is profitable to raise production, expand, introduce a new product or service, and compare the potential benefits against the associated costs.

vi.   Each decision's efficacy is evaluated based on the marginal cost calculation in cost accounting. It is a way to measure progress toward efficiency and effectiveness targets.

The constraints of marginal costs

The marginal cost has the following restrictions as a decision-making tool:

i.       Various economic considerations, such as data asymmetry, environmental and social issues, pricing discrimination, and a rise in transaction costs, might impact the cost.

ii.     The formula does not take output quality into account. For a company to profit, it is not enough to maintain a situation where marginal expenses are lower than income. Reduced sales and lower profits inevitably result from a decline in product quality brought on by increased manufacturing.

iii.   Calculational data should be acquired from trustworthy sources. Data collection from reliable sources is not always straightforward, which increases the risk of inaccurate analysis.

Factors to take into account

Marginal cost is often represented graphically as the ratio of incremental revenue to fixed expenses. Corporation and product-specific factors determine the form of the marginal cost curve, which is often "U" shaped, with the slope first decreasing as efficiencies are gained and then perhaps increasing exponentially in the future.

       i.          Differences in reporting to internal vs. external parties

Marginal cost is not something that has to be calculated for public financial statements. Internal management only utilizes marginal cost estimates to develop plans and is not included in publicly available financial statements.

In several ways, revealing a company's marginal cost could negatively impact it. Knowing the firm's cost structure would provide competitors an edge, and the market might exert pressure on the corporation if it knew the precise production levels at which operations were unprofitable for other organizations.

     ii.          Appropriate range

The concept of marginal cost emphasizes that, given the existing cost framework, adding a single more unit will result in significant cost savings. However, management should be mindful that adding new step costs or burdens to the current relevant range would result in much higher marginal costs.

Think about the landscaping equipment factory's warehouse. The storage facility can accommodate one hundred of the largest riding lawnmowers. Manufacturing the 98th, 99th, or 100th riding lawnmower may not greatly impact profit margin. However, with the production of its 101st lawnmower, the firm has reached the limit of its current storage capacity. The marginal cost of producing that extra lawnmower—the expense of finding a new place to put it—is higher than other recently produced commodities.

    iii.          Pricing approach

The marginal cost pricing concept, also known as the marginal cost theory, is an economic philosophy that, for the sake of productivity, costs for goods or services should be based on marginal costs.

Economies of scale

Enterprises that have economies of scale may have cheaper costs of manufacturing more items. Manufacturing each extra unit becomes inexpensive for a corporation with economies of scale, and the organization is encouraged to achieve the threshold where marginal revenue equals marginal cost.

A prime instance is a manufacturing facility with a large space capacity that gets more effective as more quantity is produced. Furthermore, the company may negotiate cheaper material prices with suppliers at bigger quantities, lowering variable costs.

For certain firms, when more products or services are produced, per unit expenses climb. Diseconomies of scale are believed to exist in these firms. Consider a corporation that has achieved its maximum production volume. The marginal cost would be quite expensive if it wanted to manufacture additional units since large expenditures in expanding the firm's capacity or leasing space from another factory would be necessary.

Which areas apply the marginal cost formula?

As part of normal financial analysis, professionals in various corporate finance responsibilities assess the additional cost of production. Accountants in the valuations division may execute this exercise computation for a customer, but experts in investment banking may add it as part of their financial system output.

What is the distinction between marginal and average cost?

The expenditures required to make one additional item are the marginal cost. The marginal cost frequently decreases over time as a production process gets more effective or economies of scale are discovered. However, there is typically a moment when producing one more unit becomes gradually more costly.

On the contrary, the average cost is the overall cost of production divided by the total number of units produced. Because marginal cost is not always constant from one unit to the next, average cost may vary from marginal cost. The marginal cost represents just one item, but the average cost frequently indicates all units produced.


The productivity of a business may increase or decrease as more units are produced throughout the production process. This idea of production efficiency is mirrored in marginal cost. Choices on distributing resources, optimization of manufacturing and operations, cost management in manufacturing, budgeting and profit forecasting, and so on may all be made with its help. Marginal costs are often affected by both fixed and variable expenses. However, it may consider fixed costs in cases of increasing production. Businesses should aim at producing items as long as the marginal cost is less than the marginal income.