Batch costing explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.
When a shop makes identical parts in lots rather than singly, two questions follow: what did this lot cost per piece, and how big should each lot be? Batch costing answers the first; the economic batch quantity answers the second. Both suit component makers, bakeries, garment units and anyone who makes in runs.
Batch cost = direct material + direct labour + direct expenses + set-up cost + overhead absorbed for that batch; batch cost per unit = batch cost ÷ units in the batch. The economic batch quantity is the run size where yearly set-up cost equals yearly holding cost: EBQ = √(2 × annual demand × set-up cost per batch ÷ holding cost per unit per year). Use it to size runs so that set-up savings do not drown in holding costs.
Unit costing and batch costing
Unit (single or output) costing suits one uniform product made continuously: cost per unit = total cost ÷ units. Batch costing suits products made in lots: each lot is a cost unit, with its own batch card collecting material issues, labour tickets and overhead; all units in a lot are treated as identical. Difference from job costing: a job is a single customer's order with its own specification; a batch is a lot of identical items, often made for stock. The job costing guide covers the order-based method.
Data needed
For each batch: material issued, labour hours and rate, direct expenses, the set-up (changeover) cost and the overhead rate. For the size decision: annual demand, set-up cost per batch, and the cost of holding one unit for a year (interest on money tied up, storage, insurance, loss). Tie your rates to the overhead absorption rate already used in the cost sheet. A costing and pricing analysis can set up the batch card for you.
The method
- Open a batch card with a batch number.
- Charge direct material and labour issued to the batch.
- Add set-up cost (changeover labour, scrap in trial runs, tooling).
- Absorb overhead at the predetermined rate.
- On completion, divide by good units to get cost per unit.
- For sizing, compute EBQ and compare total cost at neighbouring sizes.
EBQ resembles the economic order quantity, with set-up cost per run in place of cost per order. The simple formula treats a batch as arriving at once; where production is gradual the effective holding cost is lower and the EBQ somewhat higher.
Worked example: a maker of auto components
A shop makes a bracket. All figures assumed. Annual demand 20,000 units; set-up cost ₹2,500 per batch; holding cost ₹4 per unit per year. Direct material ₹30 a unit; direct labour ₹12 a unit; overhead absorbed ₹8 a unit.
EBQ = √(2 × 20,000 × 2,500 ÷ 4) = √(100,000,000 ÷ 4) = √25,000,000 = 5,000 units. Batches per year = 20,000 ÷ 5,000 = 4.
Cost of three batch sizes
| 2,500 units | 5,000 units | 10,000 units | |
|---|---|---|---|
| Direct material (30 a unit) | 75,000 | 150,000 | 300,000 |
| Direct labour (12 a unit) | 30,000 | 60,000 | 120,000 |
| Set-up cost | 2,500 | 2,500 | 2,500 |
| Overhead absorbed (8 a unit) | 20,000 | 40,000 | 80,000 |
| Batch cost | 127,500 | 252,500 | 502,500 |
| Cost per unit | 51.00 | 50.50 | 50.25 |
Check: 75,000 + 30,000 + 2,500 + 20,000 = 127,500; 150,000 + 60,000 + 2,500 + 40,000 = 252,500; 300,000 + 120,000 + 2,500 + 80,000 = 502,500. Per unit: 127,500 ÷ 2,500 = 51.00; 252,500 ÷ 5,000 = 50.50; 502,500 ÷ 10,000 = 50.25.
The cost per unit keeps falling as the batch grows, because the ₹2,500 set-up is spread over more pieces. Taken alone, that suggests making the largest batch. The holding cost reverses it.
Yearly cost of the decision
| Batch size | Batches a year | Set-up cost a year | Average stock | Holding cost a year | Total (₹) |
|---|---|---|---|---|---|
| 2,500 | 8 | 20,000 | 1,250 | 5,000 | 25,000 |
| 5,000 (EBQ) | 4 | 10,000 | 2,500 | 10,000 | 20,000 |
| 10,000 | 2 | 5,000 | 5,000 | 20,000 | 25,000 |
At EBQ both costs are 10,000 and the total, 20,000, is lowest. Expressed per unit made (dividing the year's holding cost by 20,000 units): ₹0.25, ₹0.50 and ₹1.00. Adding that to the batch cost per unit gives 51.25, 51.00 and 51.25, so the 5,000 batch is the cheapest all-in at ₹51.00 a unit.
What the owner decides. Run the bracket in batches of 5,000, four times a year. If the owner can halve the set-up cost to ₹1,250 (quick-change fixtures), EBQ falls to √(2 × 20,000 × 1,250 ÷ 4) = √12,500,000, about 3,536 units, and smaller runs become sensible. That is the practical reason to invest in faster changeovers.
How to read the result
Do not take the EBQ as exact; the total-cost curve is flat near the bottom, so 4,500 or 5,500 units cost little more. Adjust for machine availability, material pack sizes and customer lots. Remember the formula assumes steady demand; seasonal products need a plan by season.
Common mistakes
- Spreading set-up cost on the number of units without checking holding cost.
- Treating batch cost per unit as final when some units fail inspection; divide by good units.
- Mixing batches of different specifications under one card.
- Using the purchase price of a bought-in part as the holding cost instead of the cost to hold one unit.
- Ignoring machine time lost in set-up when the machine is the bottleneck.
Batch cost cards also feed the cost sheet for pricing.
Need help with costing your production runs?
If batch sizes are set by habit or by the largest order, we can build a batch card and a run-size review from your own set-up and holding costs through a costing and pricing analysis.
Key takeaways
- Batch cost per unit = batch cost ÷ good units; the set-up cost is shared across the lot.
- EBQ = √(2DS ÷ H); at that size set-up and holding costs are equal and total cost is lowest.
- Cost per unit falls with batch size, but holding cost rises; judge by the total.
- Cutting set-up time shrinks the economic batch.
- Batch costing differs from job costing: identical items against a customer-specific order.
Read next
- Economic order quantity and stock levels
- Job costing and pricing a customer order
- Cost sheet: prime cost to cost of sales
Disclaimer: The methods described are standard cost accounting and financial management techniques. The worked example uses an invented business and invented figures, including any tax, interest or exchange rate, which are assumptions for illustration and not current rates. Where the article refers to a legal requirement, the linked guide and the official text should be checked. This article is general information, not legal advice; check the official text before acting.