Indian tax and compliance glossary

45 terms from company law, GST and income tax, defined in one or two sentences each, with the new form numbers that apply from 1 April 2026.

Reviewed by Vijay Dhawan, Managing Partner, LexVerge LLP, on 24 October 2026 · Published 16 October 2026

Quick answer

This glossary defines 45 company law, GST and income-tax terms in plain words, with the new form numbers from 1 April 2026. Three that are often confused: GSTR-1 reports sales invoice by invoice, while GSTR-3B is the summary return that pays the tax and claims credit; AOC-4 files the financial statements within 30 days of the AGM, while MGT-7 or MGT-7A is the annual return within 60 days; TDS is deducted by the payer, while TCS is collected by the seller.

Plain definitions of the forms, numbers and terms that come up in Indian company, GST and income-tax compliance, each linked to the guide that explains it in full. Form and section numbers follow the Income-tax Act, 2025 and the Income-tax Rules, 2026, in force from 1 April 2026.

Company and LLP

SPICe+: The MCA web form used to incorporate a company. Part A reserves the name and Part B incorporates the company, with PAN and TAN allotted in the same application. Read more
RUN: Reserve Unique Name, the MCA service for reserving a company or LLP name before incorporation or a change of name. A name reserved for a change of name is held for 60 days. Read more
DIN: Director Identification Number, the unique number every company director must hold. Designated partners of LLPs use a DIN too. Read more
DSC: Digital signature certificate. A Class 3 DSC is used to sign MCA, income-tax and other government e-filings. Read more
DIR-3 KYC: KYC of every DIN holder, filed once every three financial years by 30 June, plus an intimation within 30 days of a change in mobile number, email or address. Read more
INC-20A: Declaration of commencement of business that a company with share capital files within 180 days of incorporation. Read more
AGM: Annual general meeting of shareholders, held within six months of the end of the financial year. Read more
AOC-4: The form for filing a company’s financial statements with the Registrar, due within 30 days of the AGM. Read more
MGT-7 and MGT-7A: The annual return of a company, due within 60 days of the AGM. MGT-7A is the abridged version for small companies and one person companies. Read more
ADT-1: Intimation to the Registrar of an auditor’s appointment, filed within 15 days of the meeting that appointed the auditor. Read more
DPT-3: Annual return of deposits and of loans and money received that are not treated as deposits, due by 30 June. Read more
MSME-1: Half-yearly return of amounts a company owes to micro and small enterprises for more than 45 days, due by 30 April and 31 October. Read more
Small company: A private company with paid-up capital up to ₹10 crore and turnover up to ₹100 crore, which gets lighter compliance such as the abridged annual return. Read more
One Person Company (OPC): A company with a single member, who names a nominee to take over if they die or become incapable. Read more
Section 8 company: A not-for-profit company licensed under section 8 of the Companies Act, 2013, which cannot pay dividends to its members. Read more
FiLLiP: Form for Incorporation of Limited Liability Partnership, the MCA form used to register an LLP. Read more
LLP Form 11 and Form 8: The two annual LLP filings: Form 11, the annual return, by 30 May, and Form 8, the statement of account and solvency, by 30 October. Read more
STK-2: The application to strike a company’s name off the register, filed with a government fee of ₹10,000. Read more

GST

GSTIN: The 15-character GST identification number issued to each registration. Read more
GSTR-1: The return of outward supplies, invoice by invoice, which feeds your buyers’ input tax credit statements. Read more
GSTR-3B: The summary return in which GST is actually paid and input tax credit is claimed. Read more
GSTR-2B: The auto-drafted statement of the input tax credit available to you, generated on the 14th of each month from your suppliers’ filings. Read more
GSTR-9 and GSTR-9C: GSTR-9 is the annual return, due by 31 December. GSTR-9C is the self-certified reconciliation statement required where turnover exceeds ₹5 crore. Read more
Input tax credit (ITC): GST paid on purchases that a registered business can set off against the GST it owes on sales. Read more
Reverse charge (RCM): Where the buyer, not the seller, pays GST to the government, for example on commercial rent from an unregistered landlord. Read more
LUT: Letter of Undertaking in Form RFD-11 that lets an exporter supply without paying IGST. It is valid for one financial year. Read more
E-invoice and IRN: An invoice reported to the government’s invoice registration portal, which returns an Invoice Reference Number and QR code. Required from ₹5 crore turnover. Read more
Composition scheme: A simplified GST scheme for small businesses that pay tax at a fixed rate on turnover and cannot claim input tax credit. Read more

Income tax and TDS

PAN: Permanent Account Number, the ten-character income-tax identifier for every taxpayer. Read more
TAN: Tax Deduction and Collection Account Number, needed by anyone who deducts or collects tax at source. It is applied for in Form 135 (formerly 49B). Read more
TDS and TCS: Tax deducted at source by the payer, and tax collected at source by the seller or collector, deposited with the government and credited to the other party. Read more
Form 130 and Form 131: The TDS certificates under the Income-tax Rules, 2026: Form 130 for salary (formerly Form 16) and Form 131 for other payments (formerly 16A). Read more
Form 121: The single declaration, replacing Forms 15G and 15H, that a person with nil tax gives so that no TDS is deducted. Read more
AIS and Form 26AS: The Annual Information Statement lists your income and transactions reported to the department; Form 26AS shows tax credited against your PAN. Read more
Tax year: The term the Income-tax Act, 2025 uses in place of the previous year and assessment year: income of FY 2026-27 is taxed in tax year 2026-27. Read more
Tax audit: An audit of a business’s accounts for income-tax purposes, required above ₹1 crore of turnover, or ₹10 crore where cash transactions stay within the prescribed limit. Read more
Advance tax: Income tax paid during the year in instalments, by 15 June, 15 September, 15 December and 15 March, where the year’s liability exceeds ₹10,000. Read more
Forms 145 and 146: The foreign remittance forms under the Income-tax Rules, 2026: Form 145 (formerly 15CA) is the remitter’s declaration and Form 146 (formerly 15CB) the chartered accountant’s certificate. Read more
Form 41: The form, replacing Form 10F, that a non-resident files electronically to claim treaty benefits; it is now needed in every case. Read more
12A and 80G (sections 332 and 354): Registration that exempts a charity’s income, and approval that lets its donors claim a deduction, now under sections 332 and 354 of the Income-tax Act, 2025. Read more

Registrations and IP

Udyam registration: Free government registration of a micro, small or medium enterprise, with no renewal and no expiry. Read more
IEC: Import Export Code, the ten-digit code from DGFT that a business needs to import or export goods. Read more
DPIIT recognition: Government recognition of a startup under Startup India, which is free and opens access to tax and compliance benefits. Read more
FSSAI registration and licence: Food business registration up to ₹1.5 crore turnover, a state licence up to ₹50 crore, and a central licence above that, from 1 April 2026. Read more
Trademark class: One of the 45 classes of goods and services under which trademarks are registered; a mark is protected only in the classes it is filed in. Read more

Transfer pricing

Transfer pricing: The pricing of transactions between associated enterprises, which Indian tax law requires to be at arm's length. Read more
Associated enterprise: An enterprise that participates in the management, control or capital of another, including the thirteen deemed cases in section 92A(2), such as 26% voting power or appointing an executive director. Read more
Arm's length price: The price unrelated parties would agree in uncontrolled conditions. With six or more comparables it is a range from the 35th to the 65th percentile. Read more
TNMM: Transactional net margin method, the transfer pricing method that compares net margins on cost, sales or assets with those of comparable independent companies. Read more
Form 3CEB (Form 48): The chartered accountant's report on international and specified domestic transactions. Due on 31 October 2026 for FY 2025-26; Form 48 from tax year 2026-27. Read more
TP study: The transfer pricing documentation required by Rule 10D when international transactions exceed ₹1 crore, kept ready by the Form 3CEB due date. Read more
Master file: Form 3CEAA, the group-level transfer pricing document. Part A is filed by every Indian entity of an international group. Read more
Specified domestic transaction: A related-party transaction of a unit claiming profit-linked deductions such as s.80-IA or s.10AA, or of a s.115BAB company, covered by transfer pricing above ₹20 crore a year. Read more

Frequently asked questions

What is the difference between GSTR-1 and GSTR-3B?

GSTR-1 reports your sales invoice by invoice; GSTR-3B is the summary return in which you pay the tax and claim input tax credit.

What is the difference between AOC-4 and MGT-7?

AOC-4 files the financial statements, within 30 days of the AGM; MGT-7 or MGT-7A is the annual return about shareholders, directors and capital, within 60 days of the AGM.

What is the difference between TDS and TCS?

TDS is deducted by the person making a payment; TCS is collected by the seller or collector from the buyer. Both are deposited with the government and credited to the other party’s PAN.

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New income-tax form numbers 2026 (PDF)

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Compliance calendar FY 2026-27 (PDF)

Every MCA, GST, income-tax, PF and ESI due date from April 2026 to March 2027 on one page, with the extended audit dates.

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Reviewed by Vijay DhawanManaging Partner, LexVerge LLP · reviewed on 24 October 2026 · How we write and check our guides

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Official references

The statutory sources behind this page. We keep our guidance aligned to them: verify anything time-sensitive directly.

Ministry of Corporate AffairsCompanies Act filings, forms and fee schedules
Income Tax DepartmentReturns, forms, rates and e-filing utilities
GST PortalRegistration, returns and rate notifications

Facts on this page are checked against these sources; the date of the last check is shown at the top of the page. It is general guidance, not advice on your specific facts. How we write and check our guides.