GST Complete Guide for Indian Businesses
Everything you need to know about Goods and Services Tax (GST) in India. Registration, tax rates, return filing, input tax credit, and compliance explained in simple terms.
What You'll Learn in This Guide
Chapter 1: What is GST?
Goods and Services Tax (GST) is an indirect tax levied on the supply of goods and services in India. It replaced multiple cascading taxes levied by the central and state governments, simplifying the tax structure and creating a unified national market.
- 📅 Implemented on July 1, 2017 (One Nation, One Tax, One Market)
- 🏢 Over 1.4 crore+ businesses registered under GST
- 💰 Monthly GST collection averages ₹1.5 lakh crore+ (2024)
- 🔄 Replaced 17+ indirect taxes (VAT, Service Tax, Excise, etc.)
Taxes Replaced by GST
- Central Excise Duty
- Service Tax
- Central Sales Tax (CST)
- Countervailing Duty (CVD)
- Value Added Tax (VAT)
- Entry Tax
- Luxury Tax
- Entertainment Tax
- Octroi
✓ Eliminates cascading effect of taxes (tax on tax) ✓ Reduces tax evasion ✓ Easier compliance with online portal ✓ Free movement of goods across states ✓ Lower logistics costs ✓ Boosts 'Make in India' initiative
Chapter 2: GST Registration
GST registration is mandatory for businesses whose turnover exceeds specified limits. Once registered, you get a unique 15-digit GSTIN (Goods and Services Tax Identification Number).
Who Needs GST Registration?
- Turnover Threshold: ₹40 lakhs for goods (₹20 lakhs for special category states like Himachal Pradesh, Uttarakhand, North-Eastern states)
- Service Providers: ₹20 lakhs (₹10 lakhs for special category states)
- Inter-State Sellers: Mandatory regardless of turnover
- E-commerce Sellers: Mandatory registration
- Casual Taxable Persons: Occasional sellers at exhibitions/trade fairs
- Input Service Distributors (ISD): Mandatory registration
- TDS/TCS Deductors: Government departments, e-commerce operators
Within 30 days from the date of liability (when turnover exceeds threshold). Late registration fees: ₹200 per day (₹100 CGST + ₹100 SGST).
Documents Required for GST Registration
- PAN Card of proprietor
- Aadhaar Card
- Bank account statement
- Business address proof
- Photograph
- PAN of the business entity
- Partnership deed / MOA & AOA
- Certificate of incorporation
- Authorized signatory details
- Bank account details
GST Registration Process (Step by Step)
- Step 1: Visit the GST Portal (www.gst.gov.in)
- Step 2: Click "Register Now" under "Taxpayers" tab
- Step 3: Fill Part A of Form GST REG-01 with PAN, mobile, email
- Step 4: Receive OTP and reference number
- Step 5: Fill Part B with business details, bank account, authorized signatory
- Step 6: Upload required documents
- Step 7: Submit application using DSC or EVC
- Step 8: ARN (Application Reference Number) generated
- Step 9: Verification by GST officer (3-7 working days)
- Step 10: Receive your 15-digit GSTIN certificate
Use our free GST Calculator to calculate GST inclusive and exclusive amounts, reverse charge, and tax liability.
Chapter 3: GST Tax Rates
GST has a four-tier tax structure: 5%, 12%, 18%, and 28%. Some essential goods are taxed at 0% (nil rate), while luxury and sin goods have a cess on top of 28%.
GST Rate Breakdown by Category
| GST Rate | Applicable Items |
|---|---|
| 0% | Fresh milk, eggs, curd, natural honey, fresh fruits & vegetables, bread, salt, bindi, sindoor, stamps, judicial papers, printed books, newspapers, jute, handloom products |
| 5% | Household necessities: sugar, tea, coffee (except instant), edible oils, spices, coal, fertilizers, medicines, life-saving drugs, agarbatti, postage stamps, railway tickets, economy class air tickets |
| 12% | Processed food: butter, ghee, frozen meat, fruit juice, sausage, salted peanuts, cell phones, sewing machines, umbrellas,佛像, business class air tickets, work contracts, state-run lotteries |
| 18% | Most common slab (over 60% of items): Soap, toothpaste, hair oil, ice cream, pasta, corn flakes, instant food mixes, footwear (up to ₹1000), cameras, speakers, monitors, printers, AC hotels (room tariffs up to ₹7500), telecom services, IT services, financial services |
| 28% + Cess | Luxury & Sin Goods: Pan masala, gutka, cigarettes, tobacco products, aerated drinks, luxury cars, motorcycles (>350cc), yachts, race club services, private lotteries, casinos, betting, 5-star hotel rooms (tariff > ₹7500) |
• Online gaming, casinos, horse racing: Increased to 28% on full face value • Some processed foods: Reduced to 5% • Rope and fishing nets: Reduced to 5% • Corporate guarantees: 18%
Chapter 4: Types of GST
GST in India has four components depending on whether the supply is within a state (intra-state) or between states (inter-state).
Collected by the Central Government on intra-state supplies (within same state). Revenue goes to the central government.
Example: Selling goods from Mumbai to Pune (both in Maharashtra)
Collected by the State Government on intra-state supplies. Revenue goes to the respective state government.
Example: Same as above - CGST + SGST = Total GST rate
Collected by the Central Government on inter-state supplies (between different states) and imports/exports.
Example: Selling goods from Mumbai (Maharashtra) to Delhi
Similar to SGST but applicable in Union Territories without legislature (Andaman, Lakshadweep, Dadra & Nagar Haveli, Daman & Diu, Ladakh).
Understanding GST Calculation
Product Price: ₹1,000
CGST (9%): ₹90
SGST (9%): ₹90
Total Invoice Value: ₹1,180
Product Price: ₹1,000
IGST (18%): ₹180
Total Invoice Value: ₹1,180
For intra-state transactions, the total GST rate is split equally between CGST and SGST. For inter-state, the full rate is charged as IGST.
Chapter 5: GST Returns
GST return is a document containing details of sales, purchases, output tax (tax on sales), and input tax credit (tax paid on purchases). Regular taxpayers need to file monthly and annual returns.
Types of GST Returns
Due Date: 11th of next month
Details of outward supplies (sales). Includes B2B invoices, B2C invoices, credit/debit notes, exports. Can be filed monthly or quarterly (QRMP scheme).
Due Date: 20th of next month
Monthly self-declaration summary of sales, purchases, ITC claimed, and net tax payable. Most important return for GST payment.
Due Date: 31st December (following financial year)
Annual return consolidating all monthly/quarterly returns. Mandatory for all regular taxpayers.
Due Date: 31st December (following financial year)
Self-certified reconciliation statement for taxpayers with turnover above ₹5 crores. Must be audited by CA.
For businesses with turnover up to ₹5 crores. File GSTR-1 and GSTR-3B quarterly but pay tax monthly using Form GST PMT-06.
For non-resident taxable persons (monthly return)
For e-commerce operators (monthly TCS return)
- 11th of next month: GSTR-1 (Sales details)
- 20th of next month: GSTR-3B (Payment summary)
- 31st December: GSTR-9 (Annual return)
Chapter 6: Input Tax Credit (ITC)
Input Tax Credit (ITC) allows businesses to reduce the taxes they have paid on purchases (inputs) from the taxes they need to pay on sales (outputs). This eliminates the cascading effect of tax-on-tax.
Manufacturer: Buys raw materials for ₹10,000 (GST ₹1,800) → Claims ₹1,800 ITC
Wholesaler: Buys finished goods for ₹20,000 (GST ₹3,600) → Claims ₹3,600 ITC
Retailer: Buys goods for ₹30,000 (GST ₹5,400) → Claims ₹5,400 ITC
Final Consumer: Pays ₹40,000 + GST ₹7,200 = ₹47,200 (bears final tax burden)
Conditions to Claim ITC
- ✓ You must possess a valid tax invoice from the supplier
- ✓ Goods/services must have been received by your business
- ✓ Supplier must have filed their GST return and paid the tax
- ✓ You must file your GST return within the due date
- ✓ ITC cannot be claimed on personal or exempted goods
ITC Not Available On:
- ❌ Motor vehicles (except for transport business)
- ❌ Food and beverages (unless restaurant business)
- ❌ Membership of health clubs/fitness centers
- ❌ Rent-a-cab, life insurance, health insurance (except specific cases)
- ❌ Travel benefits to employees (like foreign travel)
- ❌ Works contract services for immovable property (except plant & machinery)
ITC can only be claimed if the supplier has filed GSTR-1 and GSTR-3B. The ITC will auto-populate in your GSTR-2B. You cannot claim ITC on invoices older than 30 November of the next financial year.
Chapter 7: GST Invoicing Rules
A GST-compliant invoice is crucial for claiming ITC and avoiding penalties. Every registered taxpayer supplying goods or services must issue a tax invoice.
Mandatory Fields on GST Invoice
- ✓ Name, address, and GSTIN of supplier
- ✓ Name, address, and GSTIN of recipient (if registered)
- ✓ Invoice number (unique, sequential, alphanumeric)
- ✓ Date of issue
- ✓ HSN/SAC code (HSN for goods, SAC for services)
- ✓ Description of goods/services
- ✓ Quantity and unit (for goods)
- ✓ Value of supply (taxable value)
- ✓ Rate of GST (CGST, SGST, IGST, or UTGST)
- ✓ Amount of tax (CGST, SGST, IGST, UTGST separately)
- ✓ Place of supply (for inter-state transactions)
- ✓ Signature/digital signature
Sample GST Invoice Format
========================================
TAX INVOICE
========================================
Supplier: ABC Traders Pvt Ltd
GSTIN: 27AAAAA1234A1Z
Address: Mumbai, Maharashtra
Invoice No: INV-2024-001
Date: 15-Oct-2024
Recipient: XYZ Retailers
GSTIN: 07BBBBB5678B2Z
Address: Delhi
----------------------------------------
Item | HSN | Qty | Rate | Amount
----------------------------------------
Product A | 1234 | 10 | 1000 | 10,000
----------------------------------------
Total Taxable Value: ₹10,000
CGST (9%): ₹900
SGST (9%): ₹900
Total Invoice Value: ₹11,800
========================================
E-Invoicing Requirements
Businesses with turnover above ₹5 crores must generate e-invoices on the IRP (Invoice Registration Portal). E-invoice gets a unique IRN (Invoice Reference Number) and QR code.
Chapter 8: GST Payment Due Dates
GSTR-1: 11th of next month
GSTR-3B: 20th of next month
Tax Payment: By 20th of next month
GSTR-1: 13th of month following quarter
GSTR-3B: 22nd/24th of month following quarter
Monthly Tax Payment (PMT-06): 25th of each month
GSTR-9: 31st December
GSTR-9C: 31st December (for turnover > ₹5cr)
Composition Scheme: GSTR-4 by 30th April (annual)
TDS Deductors: GSTR-7 by 10th of next month
E-commerce TCS: GSTR-8 by 10th of next month
• Late Filing Fee: ₹50 per day (₹25 CGST + ₹25 SGST) for nil returns; ₹100 per day (₹50 + ₹50) for others. Maximum ₹5,000.
• Interest: 18% per annum on tax due from the due date.
Chapter 9: GST Penalties & Common Mistakes
Common GST Mistakes to Avoid
- ❌ Late filing of returns - Attracts interest (18%) and late fees
- ❌ Claiming ineligible ITC - Penalty of 100% of tax amount
- ❌ Mismatch between GSTR-1 and GSTR-3B - ITC disallowed
- ❌ Incorrect HSN/SAC codes - Scrutiny and penalties
- ❌ Not issuing proper invoices - Buyer can't claim ITC
- ❌ Filing with wrong GSTIN of customer - Discrepancies
- ❌ Missing e-invoicing deadlines - Invoice invalid, ITC blocked
- ❌ Not paying reverse charge (RCM) on time - Penalty + interest
GST Penalty Structure (Section 122-127 of CGST Act)
| Offense | Penalty |
|---|---|
| Non-registration (liable but not registered) | ₹10,000 or 100% of tax evaded (whichever higher) |
| Issuing invoice without supply | ₹25,000 or 100% of tax (higher) |
| Claiming excess ITC | 100% of excess amount claimed |
| Not paying collected tax | 100% of tax amount + interest |
| Fraudulent (willful evasion) | 100% to 300% of tax + possible imprisonment (6 months to 5 years) |
Chapter 10: Frequently Asked Questions About GST
Free Business Tools from Tyzo
Use these free tools to help with your GST calculations and business finance:
GST Calculator
Calculate GST inclusive and exclusive amounts for all tax slabs (0%, 5%, 12%, 18%, 28%)
Percentage Calculator
Quick percentage calculations for discounts, markups, and profit margins
Profit Margin Calculator
Calculate gross profit, net profit, and profit margin percentages
Sales Tax Calculator
Calculate pre-tax and post-tax amounts for any tax rate
Key GST Takeaways
₹40L (goods) or ₹20L (services)
5%, 12%, 18%, or 28% + cess
GSTR-1 by 11th, GSTR-3B by 20th
Only on business purchases with valid invoices
All mandatory fields + e-invoice if turnover > ₹5cr
File on time, pay correctly, claim eligible ITC
Need help with GST calculations?
Use our free GST Calculator and business tools to simplify your tax compliance.