Transitioning to GST:
Key Steps, Challenges & Process

Updated: June 2026 10 min read Milaan ERP Team
Transitioning to GST was one of the most significant tax reforms in India's history. Introduced on July 1, 2017, the Goods and Services Tax replaced a fragmented system of indirect taxes — including excise duty, VAT, service tax, and over a dozen state levies — with a single, unified tax framework. For businesses of all sizes, this shift required careful planning, system upgrades, and a thorough understanding of new compliance rules.

What is GST and Why Was Transition Necessary?

GST is a comprehensive, multi-stage, destination-based tax levied on every value addition in the supply chain. The pre-GST era in India was characterised by a complex web of taxes — central excise, customs duty, service tax, VAT, CST, entry tax, luxury tax, and more. This led to tax cascading (tax on tax), making Indian goods less competitive globally.

The transition to GST was necessary to:

  • Eliminate the cascading effect of taxes through Input Tax Credit (ITC)
  • Create a unified national market for goods and services
  • Simplify tax compliance for businesses operating across states
  • Improve tax revenue collection through better tracking
  • Make India's indirect tax system globally competitive

Did You Know?

India's GST subsumed 17 central and state taxes and 23 cesses into a single unified tax — one of the most complex tax reforms in modern economic history.

Key Steps in Transitioning to GST

The transition to GST was a multi-phased process for businesses. Here are the critical steps every business had to go through:

1

GST Registration

Migrate existing VAT/service tax registrations to GSTIN on the GST portal

2

Stock Valuation

Assess opening stock to determine eligible transitional ITC (TRAN-1)

3

IT System Upgrade

Upgrade accounting and billing software to handle GST invoicing and returns

4

Staff Training

Train finance and operations teams on GST compliance, invoicing formats

5

Vendor Alignment

Ensure all suppliers are GST-registered and provide valid GSTIN on invoices

6

Return Filing

File transitional returns (TRAN-1, TRAN-2) to claim carry-forward ITC

Challenges Businesses Faced During GST Transition

1. Understanding the New Tax Structure

GST operates under four slabs — 5%, 12%, 18%, and 28% — plus exempted and zero-rated categories. Many businesses struggled to correctly classify their goods/services under the right HSN/SAC codes and applicable tax rates.

2. Transitional Credit Claims

Claiming credit for taxes paid on pre-GST stock (TRAN-1 and TRAN-2 forms) was technically complex. Many businesses missed out on eligible credits due to filing errors or lack of awareness.

3. Technology Upgradation

Legacy accounting systems were not designed for GST compliance — invoice formats, ITC reconciliation, and GSTR filing all required major software overhauls. Small businesses particularly struggled with this.

4. Working Capital Pressures

In the initial months, mismatches in ITC claims between buyers and sellers caused delays in credit availability, creating cash flow stress especially for SMEs.

5. Anti-Profiteering Compliance

Businesses were required to pass on the benefit of reduced tax rates to consumers. The National Anti-Profiteering Authority (NAA) monitored this, adding compliance pressure.

Pre-GST vs Post-GST: Key Differences

AspectPre-GST EraPost-GST Era
Tax StructureMultiple cascading taxesSingle unified GST
Tax on TaxYes (cascading effect)No (ITC mechanism)
Interstate TradeCST + VAT complicationsSimple IGST mechanism
Return FilingSeparate state/central returnsUnified GSTR returns
Invoice FormatNo standard formatStandardised GST invoice
ComplianceMultiple registrationsSingle GSTIN (state-wise)

Transitional Provisions Under GST

The GST Act included special transitional provisions (Sections 139-142 of the CGST Act) to ensure a smooth migration:

  • TRAN-1: Allowed businesses to carry forward closing balance of CENVAT/VAT credit as opening GST ITC
  • TRAN-2: Enabled traders (without VAT invoices) to claim deemed credit on eligible goods
  • TRAN-3: For credit transfer between registered persons
  • Anti-Profiteering: Mandatory pass-through of tax reduction benefits to consumers
  • Stock Held on 1 July 2017: Special provisions to claim credit on opening stock

How Milaan ERP Simplifies GST Compliance

Milaan ERP was built ground-up for Indian GST compliance. Auto-calculate CGST/SGST/IGST, generate e-invoices with IRN, file GSTR-1 and GSTR-3B — all from one platform. 10,000+ businesses trust Milaan ERP for hassle-free GST management.

Current GST Landscape in India (2025-2026)

India's GST framework has matured significantly since 2017. Key developments include:

  • E-invoicing: Mandatory for businesses with turnover above ₹5 crore since August 2023
  • E-Way Bill: Required for goods movement above ₹50,000 interstate
  • GST 2.0 Reforms: Rationalisation of tax slabs and rate structures being actively considered
  • QRMP Scheme: Quarterly Return Monthly Payment for small taxpayers
  • IMS (Invoice Management System): New portal feature for ITC reconciliation

Frequently Asked Questions

Is GST registration mandatory for all businesses?
GST registration is mandatory if your aggregate annual turnover exceeds ₹40 lakh (₹20 lakh for special category states) for goods, or ₹20 lakh for services. Certain businesses like inter-state suppliers, e-commerce sellers, and casual taxable persons must register regardless of turnover.
Can I still claim transitional ITC in 2026?
The window for filing TRAN-1 and TRAN-2 forms has passed. However, businesses with pending disputes may seek relief through GST tribunals or courts. The Supreme Court has provided extensions in certain cases.
What is the difference between CGST, SGST, and IGST?
CGST (Central GST) and SGST (State GST) are levied on intra-state transactions — both collected simultaneously. IGST (Integrated GST) is levied on inter-state transactions and imports, collected by the Centre and later apportioned to the destination state.
How does Milaan ERP help with GST compliance?
Milaan ERP automatically calculates CGST, SGST, and IGST on every transaction, generates GST-compliant invoices, e-invoices with IRN, e-way bills, and auto-populates GSTR-1 and GSTR-3B returns. It also provides HSN/SAC code lookup and reconciliation features.

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