zSign

Q&A

Are signatures from zSign legally binding?

Yes. Signers explicitly consent to sign electronically in compliance with the U.S. ESIGN Act, UETA, and similar laws elsewhere. Every completed envelope includes a tamper-evident completion certificate. However, zSign is not a law firm and cannot guarantee enforceability in all jurisdictions, so users must determine if e-signature is appropriate for their documents.

How do I get an API key?

Calling POST /api/v1/signup returns an account and a zs_live_ API key in one call. API or MCP signup creates an account with 0 credits. Email verification grants 3 free credits, or 25 if signed up through a referral link. No credit card is required.

What does white-label include?

The $49/month white-label plan adds 100 envelopes per month and puts the user's brand on every signature request: the company name and colors appear on signing pages and emails, the zSign badge is removed, signing links run on the user's own verified domain, and emails are sent from the user's own verified email address. Includes 100 envelopes/month; additional credit packs can still be purchased. Only the team owner can subscribe.

How does the referral program work?

Every account automatically gets a referral link with no application needed. When someone signs up through that link and verifies their email, they receive 25 free credits instead of the usual 3, and the referrer earns 30% of every payment that account makes on credit packs and white-label subscriptions for as long as the account is active. Commission settles quarterly once the balance reaches $25 (US payouts only), or can be converted to zSign credits at a 1.5x bonus instantly.

What happens when I run out of credits?

Sends return 402 with {"error": "insufficient_credits"} and nothing is delivered; the debit happens before the envelope goes out, so you’re never charged for a send that didn’t happen. Top up with POST /api/v1/credits/checkout. The credits checkout endpoint returns a Stripe Checkout URL. The buyer completes payment through Stripe Checkout before purchased credits are available.