Types of Digital Signatures in India

Types of Digital Signatures in India: Overview

India recognises three classes of Digital Signature Certificates (DSC) — Class 1, Class 2, and Class 3 — plus Aadhaar-based electronic signatures (eSign). For a foundational understanding of what a digital signature is, see our introductory guide. Each type serves different purposes, from basic email verification to high-security government filings.

The classification comes from the Controller of Certifying Authorities (CCA) under the IT Act 2000. Here is what each type is, what it costs, and when you need it.

Class 1 Digital Signature

Class 1 DSCs provide the lowest level of assurance. They confirm that the signer's name and email address exist in the Certifying Authority's database. No physical identity verification is required.

Key details:

• Issued based on email ID and subscriber details only
• No in-person or video verification
• Cannot be used for legal or business documents
• Primarily used for securing email communication

Use cases:

• Email encryption and signing
• Internal communications

Current status: Most CAs in India have stopped issuing Class 1 DSCs because they are insufficient for any meaningful legal or business purpose. The CCA recommends Class 2 or higher for all practical applications.

Class 2 Digital Signature

Class 2 DSCs provide medium assurance. The CA verifies the signer's identity against a trusted database (such as the Registrar of Companies or Income Tax database) before issuing the certificate.

Key details:

• Identity verified against government databases
• Issued as a software-based certificate (PFX file) or on a USB token
• Valid for 1–2 years
• Cost: ₹500–₹1,200 per year

Use cases:

• Income Tax e-filing
• GST registration and returns
• MCA annual compliance filings
• ROC form submissions
• Company incorporation documents

Important note: As of 2023, the CCA mandated that all new DSCs must be issued on hardware tokens only (USB crypto tokens). The distinction between Class 2 and Class 3 has effectively merged for new issuances, with both now requiring hardware tokens.

Class 3 Digital Signature

Class 3 DSCs provide the highest level of assurance. The signer must appear in person (or via video verification) before the Certifying Authority. The certificate is always stored on a hardware USB token, and the private key never leaves the device.

Key details:

• Identity verified through in-person or video KYC
• Stored exclusively on a FIPS-compliant USB crypto token
• Valid for 1–2 years
• Cost: ₹1,000–₹2,000 per year

Use cases:

• E-tendering on government portals (GeM, CPPP, IREPS)
• Patent and trademark filings
• High-value contracts and agreements
• RBI, SEBI, and other regulatory filings
• Documents requiring the highest legal assurance

Why Class 3 matters: Government e-procurement portals and regulatory bodies mandate Class 3 because the hardware token ensures the private key cannot be copied, exported, or stolen through malware. This is the gold standard for digital signatures in India.

Aadhaar eSign (Electronic Signature)

Aadhaar eSign is a separate category altogether. It is an electronic signature — not a traditional DSC — authorised under Section 3A of the IT Act. Instead of issuing a long-term certificate, the eSign provider generates a temporary key pair for each signing transaction, authenticated through Aadhaar OTP or biometric verification.

Key details:

• Identity verified through UIDAI (Aadhaar) in real time
• No hardware token or pre-issued certificate needed
• Temporary signing key generated per transaction
• Cost: ₹5–₹50 per signature
• Legally valid under IT Act Section 3A

Use cases:

• Employment contracts, offer letters, NDAs
• Rent agreements and lease deeds
• Insurance policy documents and claims
• Bank account opening forms and loan documents
• Any document where both parties accept electronic signatures

Platforms like SignSetu make Aadhaar eSign accessible — upload a PDF, authenticate with Aadhaar OTP, and receive a signed document in under two minutes.

Comparison Table: All Types of Digital Signatures

Feature	Class 1	Class 2	Class 3	Aadhaar eSign
Identity verification	Email only	Database check	In-person/video KYC	Aadhaar OTP/biometric
Storage	Software	USB token (now mandatory)	USB token	Server-side (temporary)
Legal validity	Low	High	Highest	Legal validity of eSign: High (Section 3A)
Cost	₹200–500/yr	₹500–1,200/yr	₹1,000–2,000/yr	₹5–50/sign
Hardware needed	No	Yes (USB token)	Yes (USB token)	No
Renewal	Annual	1–2 years	1–2 years	Per transaction
Best for	Email only	Tax, MCA filings	E-tenders, regulatory	Contracts, HR docs
Still issued?	Rarely	Yes (merged with Class 3)	Yes	Yes

Which Type Do You Need?

For company directors and secretaries

Class 2 or Class 3 DSC. MCA requires DSC for all filings — company incorporation (SPICe+ forms), annual returns, director appointments, and charge registrations. Most directors opt for Class 3 since the cost difference is small and it covers e-tendering too.

For GST filing

Class 2 DSC or Aadhaar EVC. GST returns can be verified using either a DSC or Aadhaar-based Electronic Verification Code. If you already have a DSC for MCA purposes, use it. Otherwise, Aadhaar EVC is simpler.

For e-tendering

Class 3 DSC only. Government e-procurement portals (GeM, Central Public Procurement Portal, state PWD portals) mandate Class 3 DSCs. No alternative is accepted.

For signing business contracts

Aadhaar eSign is sufficient. Employment agreements, vendor contracts, NDAs, and client agreements do not require DSCs. Aadhaar eSign provides strong legal validity without the hardware hassle.

For signing rent agreements

Aadhaar eSign works. Several states including Maharashtra, Karnataka, and Rajasthan accept electronically signed rent agreements. Aadhaar eSign is the most practical option for tenants and landlords.

For one-time document signing

Aadhaar eSign. If you sign documents occasionally, paying ₹10–50 per signature is far more economical than buying a ₹1,500 DSC that expires in two years.

How to Get Each Type

DSC (Class 2 or Class 3):

1. Visit a licensed CA website (eMudhra, Sify, nCode, Pantasign, Capricorn)
2. Choose the class and validity period
3. Submit KYC documents (PAN card, Aadhaar, passport photo)
4. Complete video verification
5. Receive USB token by courier (1–3 working days)

Aadhaar eSign:

1. Go to an authorised eSign platform (like SignSetu)
2. Upload the document you want to sign
3. Enter your Aadhaar number
4. Verify with the OTP sent to your Aadhaar-linked mobile
5. Download the signed document — done in under two minutes

The Trend: DSCs for Compliance, Aadhaar eSign for Everything Else

The Indian digital signature ecosystem is moving in a clear direction. DSCs remain essential for specific government filings and regulatory compliance. For a detailed DSC vs Aadhaar eSign breakdown — including cost analysis and use cases — see our comparison. But for day-to-day business document signing, Aadhaar eSign is replacing DSCs because of its speed, low cost, and zero hardware requirements.

If you only need to sign business documents, start with Aadhaar eSign. If you handle MCA filings or government tenders, get a Class 3 DSC and use Aadhaar eSign for everything else.