Cost Accounting Standards (CAS)

In short

Cost Accounting Standards (CAS) are the standards issued by the Cost Accounting Standards Board (CASB) of the Institute of Cost Accountants of India (ICMAI) that lay down how each element of cost is to be measured, assigned, presented and disclosed, so that cost statements of different firms and different years are comparable. There are 24 Cost Accounting Standards, CAS 1 to CAS 24, supported by GACAP (Generally Accepted Cost Accounting Principles) for matters not covered by a specific standard. They acquire legal force through section 148 of the Companies Act, 2013 and the Companies (Cost Records and Audit) Rules, 2014, under which prescribed companies must keep cost records in Form CRA-1 and get them audited by a Cost Accountant. CAS are examined heavily in the ICMAI Intermediate and Final papers (Cost Accounting, Cost & Management Audit) and are used in practice for captive-consumption valuation, anti-dumping and subsidy submissions, regulatory tariff filings and transfer pricing.

Explained

What a CAS is and how each one is built

• A CAS is a measurement and disclosure standard for one cost element or one cost concept — not a bookkeeping rule and not a financial reporting standard (Ind AS governs financial statements; CAS governs cost statements).
• Every CAS follows the same skeleton: Introduction → Objective → Scope → Definitions → Principles of Measurement → Assignment of Cost → Presentation → Disclosures → Effective date.
• Principles of measurement decide *how much* cost is recognised (what is included, what is net of what, what is excluded as abnormal). Assignment decides *to which cost object* it goes (direct tracing, or absorption on a causal basis).
• Two ideas run through all of them: (i) abnormal and non-recurring costs are excluded from cost of production and charged to the profit and loss account; (ii) credits, subsidies, recoveries, discounts and refundable taxes are netted off the element to which they relate.
• Materiality and consistency are required — a method once chosen is followed consistently, and a change with its effect must be disclosed.

The 24 standards at a glance

Measurement rules that are asked again and again

• CAS 6 (Material): cost = purchase price + duties/taxes not creditable (GST ITC availed is excluded) + freight inward + insurance + handling, less trade discounts, rebates, refunds, duty drawback, subsidies and grants. Normal transit/storage loss is absorbed by good units; abnormal loss, demurrage, penalties and finance cost are excluded. Issues valued by FIFO, LIFO, weighted average or standard cost, applied consistently (self-manufactured material at its cost of production; spares of the nature of capital items are capitalised).
• CAS 7 (Employee): gross wages/salary, allowances, incentives, bonus, PF, ESI/insurance, gratuity and leave encashment on accrual (actuarial basis permitted), less recoveries. Normal idle time is part of employee cost; abnormal idle time and abnormal overtime premium go to P&L. Separation cost (VRS, retrenchment) is amortised over the period of expected benefit. Managerial remuneration relating to production is included.
• CAS 2 and CAS 3 (Capacity and production overheads): overheads absorbed at normal capacity utilisation; the cost of abnormal idle capacity is charged to P&L, so under-absorption from low volumes does not inflate product cost. Variable overheads are absorbed on actual production.
• CAS 16 (Depreciation): over the useful life, consistent with the Companies Act, 2013 (Schedule II useful lives for companies); cumulative depreciation cannot exceed original cost less residual value; impairment loss and depreciation on the revaluation increment are excluded from cost.
• CAS 17 (Interest): identified to the cost object where possible, but not included in cost of production; disclosed separately so that cost of sales and cost of production remain comparable across differently financed firms.
• CAS 24 (Revenue): revenue in a cost statement is net of returns, trade discounts, rebates and taxes collected (GST), to arrive at net sales realisation and hence margin per unit.
• CAS 4 draws on CAS 6, 7, 10, 11, 22 and others — it is a consolidating standard, which is why a CAS-4 certificate question is really a test of all the measurement rules together.

The legal framework in India

• Section 148, Companies Act, 2013: empowers the Central Government to direct specified classes of companies to include particulars of cost in their books and to have cost records audited by a Cost Accountant in practice (a statutory auditor cannot be the cost auditor).
• Companies (Cost Records and Audit) Rules, 2014: Rule 3 lists the covered industries in Table A (regulated sectors — electricity, petroleum, drugs and pharmaceuticals, fertilisers, sugar, telecom) and Table B (non-regulated sectors — a long list including machinery, steel, cement, rubber, chemicals, construction, education and health services, etc.).
• Cost records (Rule 5) are to be maintained in Form CRA-1, which prescribes the particulars element-wise and requires them to be kept in accordance with the Cost Accounting Standards and GACAP. That is the legal hook that makes CAS mandatory in practice.
• Thresholds (verify against the current MCA notification — these have been amended more than once): cost records if overall turnover from all products/services is ₹35 crore or more in the immediately preceding financial year; cost audit for Table A companies if overall turnover is ₹50 crore or more and turnover of the individual covered product/service is ₹25 crore or more; for Table B companies ₹100 crore and ₹35 crore respectively.
• Exemptions (Rule 4(3)): companies whose revenue from exports in foreign exchange exceeds 75% of total revenue, companies operating from a SEZ, and companies generating electricity purely for captive consumption.
• Forms and timelines: CRA-2 — intimation of appointment of cost auditor to the Central Government; CRA-3 — the cost audit report by the cost auditor to the Board (within 180 days of the close of the financial year); CRA-4 — filing of the cost audit report with the Central Government in XBRL within 30 days of receipt of the report.
• Cost Auditing Standards (a different family, do not confuse): CAS 101 Planning an audit of cost statements, CAS 102 Cost audit documentation, CAS 103 Audit evidence, CAS 104 Knowledge of business, its processes and the business environment — these govern *how the audit is conducted*, while CAS 1–24 govern *how cost is measured*.

Where CAS numbers are actually used outside the classroom

• CAS 4 certificate for valuation of goods transferred for captive consumption or to a related party — the cost of production is marked up by 110% under Rule 30 of the CGST Rules, 2017 (the same 110% rule applied under the erstwhile Central Excise Valuation Rule 8).
• CAS 5 equalized freight supports a single freight deduction/recovery across depots instead of destination-wise rates.
• Anti-dumping and countervailing-duty submissions to the DGTR, subsidy and fair-price claims, and tariff/price filings to regulators such as CERC, state electricity commissions and TRAI rely on cost statements built on CAS.
• Transfer pricing under the Income-tax Act, 2025 — the cost-plus method needs a defensible cost base, and a CAS-based cost sheet is that base.

Advantages and limitations

• Advantages: uniformity and comparability across firms and years; a clear line between normal cost and abnormal loss, so inefficiency is not hidden in product cost; defensible numbers before tax, GST, customs and regulatory authorities; better inter-firm comparison and benchmarking; a disciplined basis for pricing and make-or-buy decisions.
• Limitations: applies compulsorily only to companies covered by section 148, so most MSMEs stay outside; some standards allow a choice of method (for example material issue pricing, joint-cost basis), which reduces strict comparability; the standards cover measurement, not the design of the costing system; compliance cost and detailed record-keeping; CAS and Ind AS treat items such as interest and revaluation differently, so cost and financial figures must be reconciled.

Key points

• CASB - the Cost Accounting Standards Board of ICMAI, which issues CAS and GACAP.
• CAS 1 to CAS 24 - the complete current set; CAS 1 classifies cost, CAS 24 deals with revenue in cost statements.
• GACAP - generally accepted cost accounting principles, applied where no specific CAS covers the item.
• Section 148, Companies Act, 2013 - the statutory source of cost records and cost audit.
• CRA-1 - prescribed particulars of cost records; it mandates compliance with CAS and GACAP.
• CRA-2 / CRA-3 / CRA-4 - appointment intimation, cost audit report to the Board, XBRL filing with the Government within 30 days.
• Abnormal cost rule - abnormal idle time, abnormal losses, penalties and fines never enter cost of production.
• Normal capacity (CAS 2) - the base for absorbing fixed production overheads; abnormal idle capacity cost goes to P&L.
• Netting rule - subsidies, grants, credits, discounts, duty drawback and refundable taxes reduce the related element of cost.
• CAS 4 - cost of production for captive consumption, certified and marked up to 110% under CGST Rule 30.
• CAS 5 - average (equalized) transportation cost = total freight ÷ total quantity despatched.
• CAS 17 - interest and financing charges are excluded from cost of production and shown separately.
• CAS 15 and CAS 11 - selling and distribution overheads are never in cost of production; only the production-related share of administrative overheads is.
• CAS 9 - primary packing is production cost, secondary packing is distribution cost.
• CAS 19 - joint cost apportioned by net realisable value, physical units or market value at split-off.
• CAS 16 - depreciation on historical cost over useful life; revaluation depreciation and impairment excluded.
• CAS 101 to CAS 104 - Cost Auditing Standards, distinct from the Cost Accounting Standards.
• Cost auditor - a Cost Accountant in practice; the statutory (financial) auditor is disqualified.

Formulas and examples

Example 1 — Material cost under CAS 6. 10,000 kg purchased at a list price of ₹500/kg; trade discount 5%; GST 18% (full input tax credit available); freight inward ₹1,20,000; transit insurance ₹30,000; handling ₹25,000; demurrage penalty ₹15,000; normal transit loss 2%.

• Net purchase price = 10,000 × 500 = ₹50,00,000 − 5% = ₹47,50,000 (GST excluded, credit availed; demurrage penalty excluded as abnormal).
• Add freight 1,20,000 + insurance 30,000 + handling 25,000 → total material cost = ₹49,25,000.
• Good quantity = 10,000 × 0.98 = 9,800 kg (normal loss absorbed by good units).
• Rate = 49,25,000 ÷ 9,800 = ₹502.55 per kg.

Example 2 — CAS 4 cost of production and CGST Rule 30 value. For 10,000 units: material consumed ₹30,00,000; direct employee cost ₹8,00,000; direct expenses ₹2,00,000; production overheads ₹6,00,000 (including ₹50,000 abnormal idle-capacity cost); quality control ₹1,00,000; process R&D ₹50,000; primary packing ₹70,000; administrative overheads relating to production ₹80,000; interest ₹1,50,000; selling overheads ₹2,00,000; realisable scrap ₹60,000.

• Includible: 30,00,000 + 8,00,000 + 2,00,000 + 5,50,000 + 1,00,000 + 50,000 + 70,000 + 80,000 = ₹48,50,000.
• Excluded: abnormal idle capacity ₹50,000 (CAS 2), interest ₹1,50,000 (CAS 17), selling overheads ₹2,00,000 (CAS 15).
• Less scrap realisation 60,000 → cost of production = ₹47,90,000, i.e. ₹479 per unit.
• Assessable value = 110% × 479 = ₹526.90 per unit.

Example 3 — CAS 5 equalized freight.

• Equalized cost = 12,00,000 ÷ 40,000 = ₹30 per unit, applied uniformly to every despatch instead of the zone rates.

Example 4 — CAS 2 / CAS 3 absorption at normal capacity. Installed capacity 1,20,000 machine hours; normal capacity 1,00,000 hours; actual utilisation 90,000 hours. Fixed production overheads ₹50,00,000; variable overheads ₹20 per hour.

• Fixed rate = 50,00,000 ÷ 1,00,000 = ₹50 per hour (normal capacity, not installed).
• Fixed overhead absorbed = 90,000 × 50 = ₹45,00,000; variable = 90,000 × 20 = ₹18,00,000.
• Production overheads in product cost = ₹63,00,000; cost of abnormal idle capacity = 10,000 × 50 = ₹5,00,000, charged to the profit and loss account.

Example 5 — CAS 19 joint cost on NRV basis. Joint cost up to split-off ₹24,00,000.

• A = 24,00,000 × 17/32 = ₹12,75,000; B = 24,00,000 × 10/32 = ₹7,50,000; C = 24,00,000 × 5/32 = ₹3,75,000.

Where it is used

• Pharmaceuticals, fertilisers, sugar, petroleum, electricity and telecom (Table A regulated sectors): cost records and cost audit feed price control, tariff orders and subsidy claims — for example fertiliser subsidy and DPCO-linked costing.
• Steel, cement, automobiles, machinery, chemicals and rubber (Table B): CAS-4 certificates for inter-unit stock transfers and related-party supplies under GST.
• Mining and coal (CAS 23 overburden removal) and captive power plants (CAS 8 utilities, CAS 2 capacity) — Coal India, NTPC-type operations and cement plants with captive generation.
• Job roles: cost accountant / cost controller in manufacturing, cost audit assistant in a Cost Accountant's firm, management reporting and FP&A analyst, GST and indirect-tax executive preparing CAS-4 certificates, regulatory-affairs analyst in power and telecom.
• Professional practice: certification work — CAS-4 certificates, anti-dumping cost questionnaires for the DGTR, cost certificates for banks and for government tenders.
• Exams: ICMAI Intermediate (Cost Accounting) and Final (Cost and Management Audit, Strategic Cost Management); CA and CS cost-audit topics; PSU and manufacturing-sector interviews.

Interview questions

• Q: Who issues the Cost Accounting Standards and how many are there? A: The Cost Accounting Standards Board of the Institute of Cost Accountants of India (ICMAI); there are 24 standards, CAS 1 to CAS 24, supplemented by GACAP.
• Q: What makes CAS legally binding? A: Section 148 of the Companies Act, 2013 with the Companies (Cost Records and Audit) Rules, 2014 — Form CRA-1 requires cost records to be kept in accordance with the Cost Accounting Standards and GACAP.
• Q: What is CAS 4 used for? A: To determine the cost of production of goods transferred for captive consumption or to a related party; the certified cost is marked up to 110% to arrive at the taxable value under Rule 30 of the CGST Rules.
• Q: Is abnormal idle time part of employee cost? A: Normal idle time is absorbed in employee cost, but abnormal idle time is excluded under CAS 7 and charged to the profit and loss account.
• Q: Why are fixed production overheads absorbed on normal capacity rather than actual production? A: So that product cost is not distorted by low volumes; CAS 2 and CAS 3 require the cost of abnormal idle capacity to be charged to the period, not to the product.
• Q: How is interest treated in a cost statement? A: Under CAS 17 interest and financing charges are excluded from cost of production and shown as a separate line, so firms with different funding structures remain comparable.
• Q: Does GST paid on inputs form part of material cost? A: No, if input tax credit is availed; only non-creditable duties and taxes are added to material cost under CAS 6.
• Q: What is the difference between Cost Accounting Standards and Cost Auditing Standards? A: CAS 1 to 24 prescribe how cost is measured and disclosed; CAS 101 to 104 prescribe how a cost audit is planned, documented, evidenced and conducted.
• Q: How is primary packing different from secondary packing? A: CAS 9 treats primary packing (needed to make the product marketable) as part of cost of production, and secondary packing for transport as a distribution cost.
• Q: Can the statutory auditor of a company also be its cost auditor? A: No — section 148 requires the cost audit to be done by a Cost Accountant in practice, and the company's financial auditor is disqualified.
• Q: A plant received a government subsidy on a raw material. How is it treated? A: Subsidies, grants and incentives attributable to the material are deducted from material cost under CAS 6.
• Q: Which companies are exempt from cost audit even if they fall in the listed industries? A: Under Rule 4(3), companies whose foreign-exchange export revenue exceeds 75% of total revenue, companies operating from a SEZ, and companies generating electricity solely for captive consumption.

Common mistakes

• Confusing the Cost Accounting Standards (CAS 1–24) with the Cost Auditing Standards (CAS 101–104), or with Ind AS.
• Including interest, selling and distribution overheads, or the full administrative overhead in a CAS-4 cost of production — only the production-related administrative share qualifies.
• Absorbing fixed overheads on installed or actual capacity instead of normal capacity, and then calling the under-absorption a product cost.
• Adding creditable GST to material cost, or forgetting to deduct trade discounts, subsidies, duty drawback and scrap realisation.
• Treating abnormal losses, penalties, fines and abnormal idle time as cost, and conversely excluding normal loss (which must be absorbed by good units).
• Writing the 110% markup on cost of sales rather than cost of production, or applying it to the total instead of the per-unit cost.
• Quoting the Rule 3/Rule 4 turnover thresholds or form timelines from memory without checking the current MCA notification — they have been amended and are frequently updated.

Related topics

Cost accounting: elements of cost · Overheads: apportionment, absorption and under- or over-absorption · Cost bookkeeping: integrated accounts and reconciliation with financial accounts · Uniform costing and inter-firm comparison · Process costing (joint and by-products) · Material and labour cost control.