DocuSign API alternative · 25¢ per envelope · No monthly fee

A DocuSign API alternative at 25¢ per envelope

Try it on 25 free sandbox envelopes before you swap anything. After that, 25¢ per envelope with no seats and no minimum, sent by email and text in one call.

No monthly fee 25 free sandbox envelopes No credit card

You get a sandbox key on the next screen. Real delivery, not a simulation.

Check your email

We sent a sign-in link to . It is good for 15 minutes, and your sandbox key is waiting on the other side.

Published figures

What the two look like on a bill

 SiglioDocuSign Developer StarterDocuSign Developer Intermediate
Price per envelope25¢Not publishedNot published
Monthly fee$0$50$300
Per-seat fee$0Not publishedNot published
Minimum commitment$0Not publishedNot published
SMS deliveryIncluded at the same 25¢“Does Not Include”“Does Not Include”
Sandbox accessKey on screen in about a minute. No card, no account review.Free developer account, no cardFree developer account, no card
Webhook on every eventEvery event type, every accountNot publishedNot published
Multi-signerTwo per envelope, signed in orderNot publishedNot published

DocuSign figures are quoted from DocuSign's published developer plans page and eSignature plans page, checked on 14 September 2026. Envelope allowances are quoted as “Starting amount of 40 envelopes/month” and “Starting amount of 100 envelopes/month”; the price of an envelope beyond the allowance is not stated on either page. Sandbox wording is theirs: “Developer accounts operate in a Docusign non-production (demo) environment. They have most enterprise features enabled by default and don't expire.” A cell reading “Not published” is not stated on those pages, which is not the same as saying it does not exist. On the eSignature side, SMS delivery is sold as an add-on “Starting at $0.36/delivery” on the Business Pro plan. Prices change; check the source before relying on it.

What moving actually involves

There is no template library to migrate, because Siglio has no template system. You keep generating the same PDF you generate today and put ^S1 where the signature goes. The integration is one POST and one webhook handler, and a sandbox key to test it with costs nothing. Most of the work is deciding what to do with the signed file, since we do not keep it for you.

How it works

The e-signature API in three steps

One endpoint, one event. If your integration today is a few hundred lines of SDK, this is smaller than you expect.

01

Tag the PDF

Put ^S1 where the signature goes and ^D1 where the date goes, in white text. Invisible to the reader, findable by us.

02

POST it

One JSON request with the file and the signer. Delivery by email, text or both starts immediately.

03

Get the webhook

envelope.completed lands on your endpoint with a link to the signed PDF and its certificate.

Pricing

What it costs

WhatSiglio
Per envelope25¢
Monthly fee$0
Per seat$0
Minimum$0
SMS deliveryIncluded, same 25¢
Sandbox25 envelopes free, no card

You are billed when an envelope is created, not when it is signed. A declined or ignored envelope still costs 25¢.

Questions

Whether this is the right swap

Who should not switch?

Anyone who needs templates, bulk send, notary, identity verification, payments, CLM, or a named account team. Siglio does not have those and is not going to pretend otherwise. This is for teams whose signing need is one document, one or two signers, sent from their own software.

What do I gain?

One rate instead of a plan, no seat count to manage, text delivery at no extra charge, and an integration small enough that one person can hold it in their head.

How long does the swap take?

The API call is an afternoon. The honest long pole is your webhook handler and deciding where signed PDFs get stored, because we hand them back rather than keeping an archive for you.

Are the signatures as legally sound?

Electronic signatures have carried the same legal force as ink in the United States since 2000 under the federal ESIGN Act, and at state level under UETA. What survives a challenge is the record behind the signature, so every completed envelope carries a certificate page with the timestamp and IP address of each event. For a use case near an edge, ask your own counsel rather than a vendor page.

What happens to documents already signed elsewhere?

They stay where they are. Nothing about signing new documents here changes the ones you have already completed, and we do not need access to them.

Try it against a real document

Take a contract you send every week, tag it, and send it to yourself. 25 free envelopes, no card.

You get a sandbox key on the next screen. Real delivery, not a simulation.

Check your email

We sent a sign-in link to . It is good for 15 minutes, and your sandbox key is waiting on the other side.