GST registration
done once, done properly.

We scope whether you need regular GST, composition scheme, or voluntary registration — then file, respond to officer clarifications, and set you up with an invoice format and filing calendar that actually works. The same team continues on your monthly returns.

Realistic timeline

7–10 working days

Who signs off

Senior CA

What stays with you

Monthly return filer

Scope my GST filing

What is GST and when do you need to register?

GST (Goods and Services Tax) is a comprehensive indirect tax levied on the supply of goods and services in India. It replaced VAT, service tax, central excise, octroi and about a dozen other state and central taxes in 2017. A GST registration gives you a GSTIN — a 15-digit identification number tied to your PAN — which must appear on every invoice you issue, every return you file, and every B2B transaction you want to claim input credit on.

Registration is mandatory the moment your annual turnover crosses the threshold applicable to your state and sector (₹40 lakh for most goods businesses, ₹20 lakh for most services, ₹10 lakh in special-category states). It is also mandatory from day one if you supply across state borders, sell on e-commerce platforms like Amazon or Flipkart, run a casual taxable business, or are liable to pay GST under reverse charge. Below the threshold, registration is voluntary — but if your customers are GST-registered and want to claim input credit on what they pay you, voluntary registration is often commercially necessary.

Who needs to register, and under which scheme

GST has two main schemes for small businesses:

Regular scheme: Pay GST at applicable rates (5%, 18%, with 40% for demerit/luxury goods under GST 2.0 effective 22 September 2025), claim input tax credit on your purchases, file monthly returns. Mandatory above ₹1.5 crore turnover; the default choice for any B2B business whose customers claim input credit.
Composition scheme: Pay a flat rate on turnover (1% for traders and manufacturers, 5% for restaurants, 6% for other service providers under Section 10(2A)) with no input tax credit. Simpler filing (quarterly), lower rate, but you cannot pass GST on to customers and cannot sell across state borders. Turnover ceiling: ₹1.5 crore for goods/manufacturers/restaurants (₹75 lakh in specified special-category states), and ₹50 lakh for service providers.
Voluntary registration: Register below the threshold if your B2B customers want input credit, if you plan to grow past the threshold within the year, or if you need the GSTIN for vendor onboarding on large platforms.

The choice between regular and composition depends on who buys from you — not on which sounds easier. We walk through the economics in the scoping call.

What is included

Full GST REG-01 filing (Part A and Part B)
Authorised signatory setup with DSC or Aadhaar authentication
Clarification response within the 7-day officer reply window
GSTIN certificate delivery and verification
HSN / SAC code mapping specific to your business activity
Day-one invoice format compliant with GST rules and your billing software
Monthly / quarterly filing calendar
E-invoicing applicability check (currently mandatory for turnover above ₹5 crore)
Composition scheme eligibility assessment and election if applicable

Documents you need to prepare

PAN card of the business (sole prop uses proprietor PAN; LLP and Pvt Ltd use entity PAN)
Aadhaar of the proprietor, partners, or directors (for OTP verification)
Certificate of Incorporation or Partnership Deed (for LLP / Pvt Ltd / Partnership)
Proof of principal place of business — electricity bill, rent agreement + NOC, or ownership deed
Photographs of proprietor / partners / directors
Bank account details — cancelled cheque or first page of passbook or bank statement
Digital signature (DSC) for Pvt Ltd and LLP; Aadhaar e-sign is sufficient for proprietors
Authorisation letter / board resolution naming the authorised signatory

If registering as a Pvt Ltd or LLP, incorporation documents must match the entity's current MCA records. Address proofs must be under 60 days old. Multiple places of business across states need separate registrations.

How the process actually runs

Scoping call

A 20-minute call to confirm whether you need regular GST, the composition scheme, or voluntary registration. We also check whether you need multiple state registrations if you have offices or inventory in more than one state.

TRN generation (Part A)

We submit Part A of GST REG-01 — PAN, mobile and email — which generates a Temporary Reference Number. OTP verification on same day.

Part B filing (full application)

The main application: business details, place of business, bank details, authorised signatory, nature of business. We prepare, you review, we submit. Turnaround: 1–2 days.

Aadhaar authentication

The proprietor, partners or directors authenticate via Aadhaar OTP. Skipping this triggers a physical verification visit from the GST officer, which can add 2–3 weeks.

Officer review or clarification

The GST officer may raise clarifications (common ones: unclear address proof, mismatched signatory details, business activity description). We handle responses within the 7-day reply window.

GSTIN allotment and welcome kit

Your GSTIN certificate is issued. We send you a day-one GST playbook covering invoice format, HSN/SAC codes for your sector, filing calendar, input tax credit basics, and e-invoicing applicability.

Common mistakes businesses make

⚠ Registering voluntarily when you do not need to

If your turnover is well below the threshold (₹40L / ₹20L / ₹10L depending on state and category), voluntary GST adds monthly or quarterly filing load without necessarily helping. The main reason to register voluntarily is if your customers are GST-registered and want to claim input credit on what they pay you — if your customers are end consumers, voluntary registration is usually pure overhead.

⚠ Choosing the wrong scheme (composition vs regular)

Composition scheme is a fixed 1% / 5% / 6% rate on turnover with no input credit — suits small traders and restaurants with simple invoicing. Regular scheme allows input credit but requires monthly filings and detailed invoicing. Composition sounds cheaper but kills your competitiveness if your customers want to claim input credit. The choice depends on who you sell to, not on what sounds easier.

⚠ Missing the e-invoicing threshold

E-invoicing is mandatory for any business with turnover above ₹5 crore in any financial year since 2017-18. If you cross the threshold and continue manual invoicing, invoices are deemed invalid, buyers cannot claim input credit, and penalties apply. Many businesses only discover this at their next GST audit.

⚠ Not registering in multiple states when required

GST is state-specific. If you have warehouses, offices, or employees supplying services from multiple states, you need registration in each. Common with e-commerce sellers using Amazon or Flipkart fulfilment centres across states — the fulfilment centre is a place of business and triggers registration liability.

⚠ Skipping Aadhaar authentication to save a day

Skipping Aadhaar authentication triggers a physical verification by a GST officer, which can take 2–4 weeks and includes a site visit. Aadhaar OTP takes 30 seconds and is the single biggest time-saver in the process.

Frequently asked questions

Who is required to register for GST?

Mandatory registration applies if your annual turnover crosses ₹40 lakh (for goods) or ₹20 lakh (for services) in most states, or ₹10 lakh in special-category states (northeast and hill states). Mandatory regardless of turnover if you make interstate supplies, sell on e-commerce platforms, run a casual taxable business, or pay reverse charge GST. Voluntary registration is possible below these thresholds.

What is the difference between regular GST and the composition scheme?

Regular GST: pay GST at applicable rates (5%, 18%, with 40% for demerit/luxury goods under GST 2.0 effective 22 September 2025), claim input tax credit, file monthly returns (GSTR-1 and GSTR-3B). Composition scheme: pay a fixed low rate on turnover (1% for traders, 5% for restaurants, 6% for other service providers), no input tax credit, file quarterly returns. Composition is available for goods, manufacturers and restaurants below ₹1.5 crore turnover (₹75 lakh in specified special-category states), and separately for service providers below ₹50 lakh under Section 10(2A). The scheme is restricted for interstate supplies and e-commerce sellers.

How long does GST registration take?

Realistically 7–10 working days from document submission to GSTIN allotment, assuming Aadhaar authentication is used and no clarifications are raised by the officer. Clarifications add 3–7 days depending on complexity. Physical verification (triggered if Aadhaar auth is skipped) adds 2–4 weeks.

Can I use my residential address as the principal place of business?

Yes, provided you supply a NOC from the property owner and a current utility bill. Many sole proprietors and consultants register their residential address as the principal place of business. For regulated activities (manufacturing, warehousing of hazardous goods), separate commercial premises may be required.

Do I need separate GSTINs for multiple branches or states?

Separate registration is required for each state where you have a place of business — this includes offices, warehouses, godowns, and fulfilment centres. Within the same state, multiple branches can be covered under a single GSTIN with additional places of business declared.

What filing commitments do I take on once registered?

Regular scheme: GSTR-1 (outward supplies, monthly or quarterly), GSTR-3B (summary return and tax payment, monthly), annual return GSTR-9, reconciliation statement GSTR-9C if turnover crosses the audit threshold. Composition scheme: CMP-08 quarterly, GSTR-4 annually. Zero filings continue to be mandatory even in months with no transactions.

Can my GST registration be cancelled or suspended?

Yes. The department can suspend your GSTIN for non-filing of returns, mismatched invoices beyond thresholds, or fraudulent activity. Cancellation can be voluntary (closing the business) or departmental. Reinstatement after cancellation is possible but adds complexity — regular compliance is the simpler path.

Why work with Cosmoura on this

GST registration itself is a one-day form. The hard part is everything around it — picking the right scheme, mapping HSN or SAC codes that will not get flagged, setting up invoice templates that satisfy both GST rules and your billing software, handling officer clarifications without triggering a physical verification visit, and making sure your first few returns are clean so the department does not open scrutiny.

We handle registration as the start of a longer engagement, not as a one-shot service. The CA who files your GSTIN application also files your monthly GSTR-1 and GSTR-3B, reconciles input credit against GSTR-2B, and handles any notice that comes your way. One team, no handover.

Ready to register?

Tell us about your business — what you sell, who you sell to, which states you operate from — and we will reply within a working day with a scoped plan and realistic timeline.