FinTech Glossary

What is Marginal Cost?

Marginal cost is the additional cost a business incurs to produce one more unit of a product or service. It helps businesses understand how total cost changes when output increases.

For example, if producing 1,000 units costs ₹5,00,000 and producing 1,001 units costs ₹5,00,220, the marginal cost of the additional unit is ₹220. Marginal cost is especially useful in pricing, production planning, capacity decisions and profitability analysis.

Marginal Cost Formula

The basic formula is:

Marginal Cost = Change in Total Cost ÷ Change in Quantity

Example:

• Total cost at 10,000 units: ₹20,00,000

• Total cost at 11,000 units: ₹21,50,000

• Change in total cost: ₹1,50,000

• Change in quantity: 1,000 units

• Marginal cost: ₹150 per unit

Marginal cost usually includes variable costs such as raw materials, labour, packaging and utilities. Fixed costs are included only when output expansion requires additional fixed capacity, such as a new machine, warehouse or production line.

Why Marginal Cost Matters for Businesses

Marginal cost helps businesses decide whether producing or selling an additional unit is profitable. If the selling price or marginal revenue from the extra unit is higher than the marginal cost, producing more may improve profit. If marginal cost exceeds the revenue earned, extra production can reduce profitability.

Businesses use marginal cost for:

• Pricing and discount decisions

• Make-or-buy analysis

• Production planning

• Capacity utilisation decisions

• Break-even and contribution analysis

• Special order evaluation

It is especially useful when companies have spare capacity and need to decide whether to accept a bulk order at a lower price.

Marginal Cost vs Average Cost

Marginal cost and average cost answer different questions.

Marginal cost asks: What will it cost to produce one more unit?

Average cost asks: What is the cost per unit across all units produced?

A product can have a low marginal cost but a high average cost if fixed costs are large. For example, a software product may have high development cost but very low cost for each additional user. In such cases, marginal cost becomes critical for pricing and scaling decisions.