Digital Signature Explained With SignNow Security Guide

Award-winning eSignature solution

What a digital signature is

A digital signature is a cryptographic way to sign an electronic document and prove who signed it and whether the file changed after signing. It uses public key infrastructure, or PKI, to create a unique signature tied to the signer’s private key and the document’s hash. When someone signs, the system records identity details, time stamps, and document integrity data. A verifier can then confirm the signature with the signer’s public key and detect tampering.

Why digital signatures matter

Digital signatures help businesses reduce paper handling, speed approvals, and preserve evidence of intent. Under ESIGN and UETA, they can be enforceable when attribution, consent, and record integrity are documented, which makes them useful for contracts, approvals, and regulated workflows.

Why teams look for DocuSign alternatives

Digital signature pain points

Signer identity can be disputed if authentication is too weak or records do not clearly show who completed the signing action.
Documents may lose evidentiary value when audit trails are incomplete, missing timestamps, or lacking device and IP details.
Regulated teams can create compliance gaps if retention, access control, or BAA requirements are not configured correctly.
Users may confuse a drawn electronic signature with a cryptographic digital signature, which can affect security expectations.

Real estate

Used for lease agreements, rental applications, disclosures, and closing paperwork that need fast turnaround and clear signer intent.

Healthcare

Used for patient forms, consent records, and HIPAA workflows that require access controls, audit trails, and retention.

People who benefit most

Teams in property operations use digital signatures to move leases, addenda, and tenant forms through remote signing without delaying occupancy or renewals.
Healthcare administrators use them for intake packets, consent forms, and release authorizations while keeping audit trails and retention aligned with HIPAA workflows.

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Cryptographic binding

Creates a cryptographic link between the signer and the document, helping verify identity and detect post-signing changes.

Audit trail

Records timestamps, signer details, and document events in a tamper-evident history that supports review and dispute handling.

Cross-device signing

Supports mobile and desktop signing so documents can move without printing, scanning, or in-person meetings.

Flexible routing

Helps teams route documents in sequence or parallel, which reduces delays in approvals and acknowledgments.

Record integrity

Stores signed files with integrity controls that help preserve the final record for later retrieval or review.

Access control

Works with role-based access and authentication options that support controlled signing in business and regulated settings.

Connected systems and workflows

Connected systems move signed documents into the tools teams already use, reducing manual entry and keeping records aligned across departments.

How it works step by step

The signing flow is simple for users, but each step adds identity, integrity, and evidence to the final record.

Open document: The signer opens the document and reviews the content before signing.
Verify identity: The system verifies identity with the chosen authentication method.
Create signature: A cryptographic hash is created and signed with the private key.
Seal record: The signed file is sealed and stored with an audit trail.

Quick signing setup

Use a short setup sequence to prepare a document, route it, and keep the completed record organized.

Upload file:
Upload the document you want signed.
Add fields:
Place signature fields and required initials.
Assign signers:
Choose recipients and set the signing order.
Send request:
Send the document for electronic signature.
Save record:
Download the completed file and audit trail.

Setting	Recommendation
Authentication method	SMS OTP for higher assurance
Signature type	Cryptographic digital signature
Audit trail	Enable full event logging
Document retention	6 years for HIPAA records
Encryption	TLS 1.2/1.3 and AES-256

Platform and device support

signNow works across major browsers and mobile devices, so users can sign from desktop or phone without special hardware.

Desktop browsers Chrome, Firefox, Safari, and Edge.
Operating systems Windows, macOS, iOS, and Android.
Mobile devices iPhone, iPad, and Android phones.

For regulated deployments, managed devices, SSO, and controlled access matter more than the device itself. Browser updates, secure network settings, and retention policies should stay aligned with internal IT and compliance rules.

Security and compliance

Transport security:

TLS 1.2/1.3 in transit

Storage encryption:

AES-256 at rest

Security certification:

SOC 2 Type II available

Information security:

ISO 27001 certified

Healthcare compliance:

HIPAA support with BAA

Regulated records:

21 CFR Part 11 support

Property operations

A property operations team needed faster lease execution across multiple locations.

Used signNow to route leases remotely.
Reduced delays from paper handoffs.

The team kept lease workflows moving without requiring in-person signatures, while preserving a clear record of who signed and when. That helped support faster turnaround and cleaner document handling across locations.

Healthcare admin

A healthcare organization needed patient forms and consent records that fit HIPAA workflows.

Used signNow with BAA support.
Kept audit trails and retention in place.

The organization could collect signatures on intake and consent forms while maintaining access controls, audit history, and retention practices aligned with HIPAA expectations. That reduced manual processing without changing the recordkeeping model.

Best practices for signing

Strong signing workflows depend on identity proofing, record control, and retention rules that match the document’s legal and business risk.

Match authentication to risk

Use stronger authentication for contracts, healthcare forms, and other records where signer attribution may be challenged later.

Preserve evidence

Keep a complete audit trail with timestamps, signer details, and document history for every signed file.

Define retention up front

Set retention rules before rollout so signed records stay available for the required business or regulatory period.

Restrict record access

Limit access to signed records with role-based permissions, especially when documents contain PHI, PII, or financial data.

FAQ and troubleshooting

These answers focus on plan limits, compliance rules, and recordkeeping issues that affect digital signature workflows in practice.

If a signer says the document was not received, check the recipient email, resend from signNow, and confirm the workflow status in the Business or Enterprise plan.

If HIPAA records are involved, use a BAA, enable access controls, and keep signed documents for 6 years under 45 CFR 164.530(j)(2).

If a court challenge is likely, rely on the audit trail, signer authentication details, and tamper-evident record history to support ESIGN and UETA enforceability.

If a workflow needs bulk sending, use Business Premium or higher, because bulk send is included there, not in the Business plan.

If a regulated record needs stronger controls, use 21 CFR Part 11 features such as timestamps, access controls, and document history retention.

If a signer used a mobile device, the signature can still be valid under ESIGN and UETA when intent, attribution, and record retention are preserved.

signNow	DocuSign	Adobe Acrobat Sign	Criteria
ESIGN and UETA	Yes	Yes	Yes
Audit trail	Yes	Yes	Yes
HIPAA support	Yes	Yes	Yes
Envelope cap	Unlimited	Tiered	Tiered

Day 0:

Set up the account and prepare the first document.

Day 1:

Send the first signature request and confirm delivery.

Week 1:

Onboard the core team and review permissions.

Week 2:

Add templates, routing rules, and retention settings.

HIPAA retention:

Keep signed PHI records for 6 years.

ESIGN consent:

Capture electronic consent before first use.

Part 11 records:

Retain secure history for regulated records.

Trial period:

7-day free trial, no credit card required.

Risks of poor implementation

Weak attribution

May weaken enforceability.

Missing audit trail

May fail evidentiary review.

Retention gap

May violate retention rules.

Access control failure

May trigger compliance findings.

Signer authentication:

Confirms the signer through the selected authentication method.

Timestamp capture:

Captures UTC timestamps for each signing event.

Document hashing:

Calculates a document hash before and after signing.

Tamper-evident sealing:

Applies a tamper-evident seal to the final file.

Audit trail storage:

Stores the event history with the signed document.

Audit trail export:

Exports the audit trail for review or evidence.

	Plan / Feature	signNow	DocuSign	Adobe Sign	PandaDoc
Starting price	$8/user/mo	$15/user/mo	$14/user/mo	$19/user/mo	$15/user/mo
Free trial	7 days	Not verified	Not verified	Not verified	Not verified
Bulk send	Yes	Not verified	Not verified	Yes	Not verified
Audit trail	Yes	Yes	Yes	Yes	Yes
Envelope cap	No cap	100/year	Not verified	Not verified	Not verified

28M+Documents signed

13+Years in business

4.6/5Average G2 rating