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GST billing guide

GST invoice format என்றால் என்ன?

Short answer

GST-இணக்கமான tax invoice-இல் விற்பனையாளர் மற்றும் வாங்குபவரின் GSTIN, invoice number மற்றும் தேதி, delivery முகவரி, HSN/SAC codes, வரிக்குரிய மதிப்பு, CGST/SGST அல்லது IGST விகிதம் மற்றும் தொகை, மற்றும் மொத்த தொகை இருக்க வேண்டும். Nidhi Books இந்த அனைத்து fields-ஐயும் தானாக நிரப்பி Rule 46-இன் கீழ் valid format-இல் PDF உருவாக்குகிறது.

Updated 2026-07-09 · 399Apps · General GST information, not tax advice

How to make a GST-compliant invoice: step by step

Whether you use software or a template, a valid GST invoice needs the same fields in the same logical order.

  1. 1

    Add your business details and GSTIN

    Put your trade name, address and GSTIN at the top, with the title "Tax Invoice".

  2. 2

    Assign a unique invoice number and date

    Use a consecutive serial number (maximum 16 characters, letters/numbers/hyphen/slash) unique for the financial year, plus the invoice date.

  3. 3

    Enter the customer details and place of supply

    Add the recipient’s name, address, GSTIN (if registered) and the place of supply — this decides whether you charge CGST+SGST or IGST.

  4. 4

    List the items with HSN/SAC

    For each line add the description, HSN/SAC code, quantity, unit, rate and taxable value (after any discount).

  5. 5

    Apply the correct GST

    Charge CGST + SGST for intra-state supplies or IGST for inter-state supplies, showing the rate and amount for each tax head.

  6. 6

    Show totals, reverse charge and signature

    Add the total taxable value, total tax, invoice total (in figures and words), whether tax is payable on reverse charge, and the authorised signature or digital signature.

What is a GST invoice?

A GST invoice (tax invoice) is the document a registered supplier must issue for a taxable supply of goods or services. It records what was sold, to whom, at what value, and how much GST applies — and it is the basis on which the buyer claims input tax credit. The mandatory contents are set out in Rule 46 of the CGST Rules.

Mandatory fields in a GST invoice (Rule 46)

A compliant tax invoice must contain:

  • Supplier’s name, address and GSTIN.
  • A consecutive invoice number, unique for the financial year (up to 16 characters).
  • Date of issue.
  • Recipient’s name, address and GSTIN (or state and place of supply if unregistered and value above ₹50,000).
  • HSN code for goods or SAC for services.
  • Description, quantity/unit, and total value of goods or services.
  • Taxable value after discount, the GST rate, and the tax amount split into CGST, SGST/UTGST or IGST (and cess if any).
  • Place of supply and the state code for inter-state sales.
  • Whether GST is payable on reverse charge.
  • Signature or digital signature of the supplier or authorised person.

Tax invoice vs bill of supply

A tax invoice is issued when GST is charged on a taxable supply. A bill of supply is issued instead when no GST is charged — for example by a composition dealer or for exempt/nil-rated goods — and it omits the tax break-up. Charging GST on a bill of supply, or issuing a bill of supply where a tax invoice is required, is a compliance error.

Time limits to issue a GST invoice

For goods, the invoice must be issued on or before the removal or delivery of the goods. For services, it must be issued within 30 days of supplying the service (45 days for banks, insurers and financial institutions). Issuing invoices late or out of sequence can create GST and reconciliation problems.

Invoice numbering rules

Invoice numbers must be consecutive, unique for the financial year, and no longer than 16 characters using only letters, numbers, hyphen and slash. You may run multiple series (for example per branch or per type), but each must be unique and unbroken — gaps or duplicates raise questions during scrutiny.

How 399Apps helps

Nidhi Books (by 399Apps) generates GST-compliant tax invoices automatically — correct invoice numbering, HSN/SAC, place-of-supply-based CGST/SGST or IGST, a UPI QR on the PDF, and e-invoice/IRN where required — so every bill meets Rule 46 without manual checking.

FAQ

GST invoice format குறித்து அடிக்கடி கேட்கப்படும் கேள்விகள்

GST invoice-ல் எந்த fields கட்டாயம்? +
கட்டாய fields: supplier பெயர், முகவரி மற்றும் GSTIN; invoice எண் மற்றும் தேதி; buyer பெயர், முகவரி மற்றும் GSTIN (B2B-க்கு); place of supply; HSN/SAC code; taxable value; applicable GST விகிதம் மற்றும் தொகை; மொத்த invoice மதிப்பு மற்றும் கையொப்பம்.
B2C invoice-ல் buyer-ன் GSTIN தேவையா? +
இல்லை, B2C (unregistered buyer) invoices-ல் buyer-ன் GSTIN போடுவது கட்டாயமில்லை. ஆனால் ₹2.5 லட்சத்திற்கு மேல் inter-state B2C விற்பனைக்கு buyer-ன் பெயர், முகவரி மற்றும் state code போட வேண்டும்.
GST invoice English-ல் மட்டுமே இருக்க வேண்டுமா? +
GST விதிகளில் English மட்டும் கட்டாயம் என்று இல்லை, ஆனால் invoice tax authorities புரிந்துகொள்ளும்படி readable ஆக இருக்க வேண்டும். பெரும்பாலான businesses English அல்லது bilingual format பயன்படுத்துகின்றன.
Credit note மற்றும் debit note எப்போது வழங்கப்படும்? +
Credit note: original invoice-ல் taxable value அல்லது tax குறைக்க — திரும்பப் பெறல் அல்லது தள்ளுபடிக்கு. Debit note: taxable value அல்லது tax அதிகரிக்க — குறைவாக bill செய்யப்பட்ட invoices-க்கு.
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