Initial and Sign
Developer API

Connect your website to Initial and Sign.

Let your existing product hand off a document, signer details and client reference to Initial and Sign, then let the account holder continue through the normal secure signing workflow.

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Version 1

What this integration does

Your website can create an integration request that preloads the send-document workflow with a PDF, a client reference, a message and one or more signers. The sender still logs into Initial and Sign, confirms the details, places fields and sends the document.

What remains inside Initial and Sign

  • User authentication and organisation permissions.
  • Signature field placement and document review.
  • Electronic consent, audit trail and legal workflow.
  • Email delivery, reminders and status tracking.

Good fit for

  • CRM and conveyancing systems.
  • Client portals that produce PDF forms.
  • Websites that already know the signer names and emails.
  • Teams that want less retyping before sending a document.

Typical connection flow

  1. Your website prepares the package: PDF, client reference, signer names and signer emails.
  2. Your server creates an integration request using your partner API credentials.
  3. Initial and Sign returns a secure start URL for the sender.
  4. The sender opens the URL, signs in if required, reviews the preloaded details and continues.
  5. The normal Initial and Sign workflow handles field placement, consent, sending, tracking and audit history.

Example request

Send the request from your server, not from browser JavaScript. Use multipart form data when attaching the PDF.

POST https://www.initialandsign.com/cgi-bin/api/v1/integration-requests.pl
Headers:
  X-IAS-Api-Key: your_partner_key
  X-IAS-Timestamp: 2026-08-20T10:15:00Z
  X-IAS-Signature: hmac_sha256_signature

Form fields:
  payload = {
    "external_reference": "20260108_9HopebushStreet_Lara3212",
    "idempotency_key": "crm-20260108-9hopebush-3212",
    "document_title": "Client Authority - 9 Hopebush Street",
    "message_to_signers": "Please review and sign this authority.",
    "signers": [
      {
        "name": "Sukhwinder Kaur Deol",
        "email": "sukhwinderdeol21@gmail.com"
      },
      {
        "name": "Gursewak Singh Deol",
        "email": "gursewak@example.com"
      }
    ]
  }
  file = Client Auth 9Hopebush Signed.pdf

The API also accepts the conveyancing handoff field names directly or inside the JSON payload: client1, client2, client_email_address, client_reference, and attachment. These are normalised into the Initial and Sign document title, external reference, signer list and PDF package.

Example response

{
  "success": true,
  "integration_request_id": 123,
  "status": "received",
  "expires_at": "2026-08-21T10:15:00Z",
  "start_url": "https://www.initialandsign.com/pages/integration-start.html?request_token=..."
}

Security model

Partner systems can create the request, but the package is not attached to an organisation until the Initial and Sign account holder authenticates. This keeps the final authority with the sender account and organisation.

Duplicate handling

Use a stable idempotency key for each source document. If the same package is submitted again within the request window, Initial and Sign can return the original request instead of creating a duplicate.

Signer limits

Standard accounts can be limited to a sensible number of signers, such as five. Enterprise accounts can be configured for larger workflows where required.

Adding the link to your website

Most integrations use a button such as Send with Initial and Sign. The button calls your own server first, your server creates the integration request, and then you redirect the user to the secure start_url returned by Initial and Sign.

If you have a logo or preferred button artwork, use it beside the button text on your own site. Keep the API credentials on your server only; never place partner keys or signing secrets in front-end code.