Open Source eSignature API for SignNow
Award-winning eSignature solution
What an open source eSignature API does
An open source eSignature API is a developer-facing interface that lets software send documents for electronic signing, collect signer actions, and store proof of the transaction. It works by creating a signing request, routing the document to one or more recipients, capturing consent and signature events, and returning status updates through API calls or webhooks. In U.S. use, the API supports records that can be attributed to a signer, time-stamped, and retained with an audit trail for ESIGN and UETA purposes.
Why it matters for U.S. transactions
It reduces manual routing, speeds document turnaround, and centralizes evidence for signed records. Under ESIGN and UETA, electronic signatures can be enforceable when intent, attribution, and record retention are documented.
Common implementation pain points
Maintaining a defensible audit trail across custom workflows can be difficult when events are logged inconsistently. Signer identity checks may be too weak for healthcare, finance, or other higher-risk transactions. Document templates and field mapping can break when the API is connected to multiple systems. Retention rules, consent records, and export formats often need manual governance to support compliance reviews.
Who uses it and what it covers
Real estate
Real estate teams use it for leases, disclosures, and rental applications that need fast turnaround.
Healthcare
Healthcare organizations use it for intake forms, consent records, and HIPAA-covered patient documents.
Typical users and real-world roles
Operations leaders at multi-branch real estate firms use signNow to standardize lease and disclosure signing across desktop and mobile workflows. They usually need fast routing, reusable templates, and a clear audit trail that supports remote closings and tenant onboarding without paper handling. NetSuite operations managers and ERP administrators use signNow when approvals must move with invoice, vendor, or order data already stored in business systems. Xerox’s customer story shows how integrated routing helps place the right signatures on the right documents in the right formats.
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Key features and practical benefits
Open source eSignature API workflows work best when they balance routing, evidence, and signer experience without adding unnecessary complexity.
Workflow routing
Route documents through signing steps, reminders, and status updates without manual follow-up. The API keeps the process structured, so teams can track who signed, who is pending, and which document version is current.
Audit evidence
Capture signer actions, timestamps, and document history in a format that supports later review. This helps organizations preserve evidence for ESIGN, UETA, and internal recordkeeping policies.
Reusable templates
Use templates to reuse approved document layouts and reduce setup time for recurring agreements. This is useful for leases, consent forms, and standard approvals that follow the same fields and signer order.
Mobile signing
Send signing requests from mobile or desktop workflows without changing the core process. The same API-driven document can move across devices while keeping the signing record intact.
Identity checks
Apply signer verification steps that fit the transaction risk, from simple email access to stronger identity checks. That flexibility matters when one workflow serves both low-risk and regulated documents.
Controlled records
Keep document handling inside a controlled system instead of moving files between email threads and shared drives. That reduces version confusion and makes it easier to govern retention and access.
How the signing flow works
The API moves a document from preparation to completion in a controlled sequence, while each event is recorded for later review.
Prepare: Create the document and define signer order. Send: Send the signing request through the API. Capture: Collect signatures, timestamps, and status updates. Archive: Store the completed record with audit evidence.
Quick setup steps
A short implementation path helps teams move from template design to signed records without overcomplicating the first release.
Set up:
Create a reusable document template. Configure:
Map signer fields and roles. Launch:
Send the document through the API. Review:
Monitor completion and store the final file.
Recommended workflow settings
A controlled setup keeps identity, retention, and encryption aligned with U.S. recordkeeping and regulated document needs.
| Setting | Recommendation |
|---|---|
| Authentication method | SMS OTP with SSO fallback |
| Signature type | SES for routine workflows |
| 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 requirements
Use a modern browser or mobile device with secure network access to sign, send, and review documents through the API.
Desktop browsers Chrome, Firefox, Edge, and Safari. Operating systems Windows 11, macOS, iOS, Android. Connection security TLS 1.2 or TLS 1.3 required.
For enterprise deployments, managed Windows, macOS, iOS, or Android devices work best when paired with controlled access, SSO provisioning, and current TLS settings. Browser support should stay current with Chrome, Firefox, Safari, or Edge to avoid signing or rendering issues.
Security and compliance safeguards
Encryption:
Storage protection:
Controls:
Certification:
Healthcare:
Regulated records:
Real-world examples and outcomes
Customer stories show how signing workflows fit ERP, real estate, and service operations without changing the underlying legal record.
ERP operations
A NetSuite operations leader needed signatures tied to ERP data and document format rules.
- Xerox used signNow with NetSuite.
- Right signatures, right documents, right formats.
The workflow kept approvals aligned with system data, which reduced format errors and improved routing consistency across document types.
Real estate
A real estate founder needed mobile execution for leases and related forms across locations.
- Martin Properties processed documents online.
- Mobile and offline signing supported field work.
The team handled documents without paper delays, while maintaining compliance-focused records and a practical signing process for remote work.
Best practices for implementation
A careful rollout focuses on evidence, identity, and record control before expanding to more documents or departments.
Lock down templates before launch
Match authentication to document risk
Keep evidence together
Test failure paths early
FAQ and troubleshooting
These answers focus on plan limits, compliance needs, and workflow issues that affect implementation and record defensibility.
signNow Business starts at $8/user/mo on annual billing. Business Premium adds bulk send, and Enterprise adds advanced signer authentication. All paid plans include unlimited users, a 7-day free trial, and audit trails for ESIGN and UETA workflows.
signNow supports ESIGN and UETA compliance for U.S. electronic signatures. For healthcare records, HIPAA use requires a BAA, plus access controls, audit controls, and retention of signed documents for 6 years under 45 CFR §164.530(j)(2).
The platform records signer activity, timestamps, and document history. For stronger evidentiary support, use a workflow that preserves the completed PDF, delivery receipts, and exportable audit data so the record can support non-repudiation and court review.
Bulk send is included in Business Premium and higher tiers. If you need large-scale distribution, check whether your workflow also needs templates, quick invite links, or advanced integrations before choosing a plan.
For regulated records, use the Site License or an Enterprise setup with the needed add-ons. signNow lists HIPAA and 21 CFR Part 11 support, while eIDAS QES is available on Site License for higher-assurance EU workflows.
If a signer cannot complete the flow on mobile, verify browser support and device settings first. signNow works with Chrome, Firefox, Safari, and Edge on Windows, macOS, iOS, and Android, with TLS 1.2/1.3 required for secure access.
Vendor comparison at a glance
A short comparison helps separate baseline legal support from plan-level differences in pricing, sending limits, and workflow features.
| signNow | DocuSign | Adobe Sign | PandaDoc |
|---|---|---|---|
| ESIGN and UETA | Yes | Yes | Yes |
| Starting price | $8/user/mo | $15/user/mo | $14/user/mo |
| Free trial | 7-day trial | Trial available | Trial available |
| Bulk send | Business Premium | Yes | Yes |
| Audit trail | Yes | Yes | Yes |
Rollout and retention timeline
This timeline combines implementation milestones with retention and consent facts that affect U.S. recordkeeping and regulated workflows.
Setup day:
First send:
Team onboarding:
Free trial:
HIPAA retention:
ESIGN consent:
Part 11 records:
Rollout review:
Risks of improper implementation
Weak evidence
Signer dispute
HIPAA exposure
Record loss
What happens inside the audit trail
The audit trail captures identity, timing, and document integrity so the signing record can be reviewed later.
Authenticate:
Timestamp:
Hash:
Seal:
Store:
Export:
Pricing and plan snapshot
Pricing varies by plan tier, billing cycle, and compliance needs, so the table below keeps to verified entry-level data.
| signNow | DocuSign | Adobe Sign | PandaDoc | HelloSign | |
|---|---|---|---|---|---|
| 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 | Business Premium | Not verified | Not verified | Not verified | Not verified |
| Audit trail | Yes | Yes | Yes | Yes | Yes |
| HIPAA compliance | BAA required | BAA available | BAA available | Not verified | Not verified |
Key performance indicators that demonstrate SignNow's proven track record.