Most lists of DocuSign alternatives are lists of other SaaS products. You swap one per-envelope subscription for a cheaper one and carry on. This is the other list: the open-source platforms you can run on your own server, where the recurring cost is the machine rather than the seat count.
That is a real option now in a way it was not three years ago. It is also not a free lunch, and the last section of this post is about the part nobody selling you a self-hosted signing tool wants to dwell on.
Why people leave
Two reasons, in roughly this order.
Per-envelope pricing meets an unexpected volume. E-signature pricing is usually a seat price plus an envelope allowance, and the allowance is where it bites. A team that signs a predictable ten contracts a month is fine. A team that suddenly onboards two hundred contractors is not, and the overage conversation arrives before the budget one.
The documents stop being ordinary. Once you are signing something you would rather not hand to a third party at all, the question changes from "what does this cost" to "where does this live". That is the self-hosting argument, and it is the stronger of the two.
The three worth knowing
All three are AGPL-3.0, actively developed, and deploy from a container.
| Stars | Stack | Best at | |
|---|---|---|---|
| DocuSeal | 18.2k | Rails + Postgres | Building forms fast |
| Documenso | 14.3k | Next.js + Postgres | Signing workflows and an API |
| OpenSign | 6.8k | React + Node + MongoDB | A DocuSign-shaped UI |
Star counts are a proxy for how many people will have hit your problem before you do, which for self-hosted software matters more than feature checklists.
DocuSeal
The most popular of the three, and the one to try first if your work is mostly "put fields on a PDF and send it to two people". The field builder is genuinely good: twelve field types, drag and drop, multiple submitters with their own field sets. It generates signed PDFs with verification, and there is an API and webhooks for wiring it into something else.
It is a Rails application with Postgres behind it and no other moving parts, which makes it the least demanding of the three to keep alive.
Documenso
Positions itself directly as the open-source DocuSign, and the difference from DocuSeal shows up in the signing layer rather than the form builder. It does real PKCS#12 document sealing, meaning the signed PDF carries a cryptographic signature from a certificate you control, not just a rendered image of a signature.
If your reason for leaving DocuSign is that you need signatures to hold up technically rather than just look official, this is the one to read about first. It also has the more developed team, template and API story.
OpenSign
Smaller and younger, and the closest of the three to a DocuSign-shaped interface, which matters if you are moving non-technical colleagues across. React and Node with MongoDB underneath, so it is the odd one out if the rest of your infrastructure speaks Postgres.
What they cost to run
The honest number is not zero, and it is not the sticker price of a VPS either.
| App RAM | Database | Total | |
|---|---|---|---|
| DocuSeal | 1 GB | Postgres | ~2 GB |
| Documenso | 2 GB | Postgres | ~3 GB |
So a small server runs either comfortably. On a usage-priced host that is one line item; on a fixed-capacity plan it runs inside capacity you already bought, which is the arrangement that makes self-hosting a second and third internal tool cheap rather than incremental.
The cost that is easy to miss is not the RAM. It is that you now own uptime, upgrades and backups for a system that holds executed contracts. A signing platform is a bad place to discover your backup job has been failing quietly, because the documents in it are the ones you will need precisely when something has gone wrong.
Both stacks are in our catalogue as open-source compose templates: Documenso and DocuSeal. The compose files are vanilla and run anywhere.
The part self-hosting does not replace
This is the section that decides whether the rest of the post is useful to you.
DocuSign does not sell a signature widget. It sells a signature widget wrapped in identity verification, tamper-evident audit trails, retention guarantees, and a compliance apparatus that exists to make a signature defensible when somebody disputes it later. Self-hosting replaces the widget.
Some of the wrapper you can rebuild. Audit trails and tamper evidence are features these projects have. Identity verification, in the sense of proving that the person who clicked was the person named, generally is not, and it is the part that gets tested in a dispute.
Electronic signatures are legally recognised in both the US and the EU, so the question is never "is an e-signature valid". It is what level of assurance the specific thing you are signing needs, and whether that level requires a third party whose whole job is attesting to it. For a contractor NDA the answer is usually no. For something that ends up in front of a court or a regulator, ask a lawyer rather than a blog post, including this one.
The honest summary: self-host when the driver is cost, data residency, or volume. Think harder when the driver is compliance, because compliance is the thing you were buying.
When to stay
Three cases where the migration is not worth it:
- You sign rarely. Ten envelopes a month does not justify a service you have to keep patched.
- Your counterparties expect it. In some industries the DocuSign envelope is itself a signal, and arriving with a self-hosted link creates a conversation you did not want to have.
- Nobody owns the infrastructure. If there is no person whose job includes noticing that a container has been restarting for a week, that person will turn out to have been you, at the worst moment.
Frequently asked questions
What is the best open-source DocuSign alternative?
DocuSeal for most teams, on the strength of its form builder and how little it needs to run. Documenso if you need cryptographic PKCS#12 sealing or a real API. OpenSign if a familiar DocuSign-like interface matters more than either.
Are open-source e-signature tools legally valid?
Electronic signatures are recognised by law in the US and the EU regardless of which software produced them. What varies is the level of assurance required for a given document, and the higher levels can involve a qualified third party that no self-hosted tool can be on its own. Treat this as a question for your counsel, not your infrastructure team.
Is Documenso really free?
The self-hosted edition is AGPL-3.0 and free to run. Documenso also sells a hosted version, which is the usual open-core arrangement: the code is genuinely open, and you are paying for somebody else to operate it. Note that AGPL has obligations if you offer the software to others over a network.
How much does it cost to self-host an e-signature platform?
Around 2 to 3 GB of RAM plus a Postgres database, so a modest server. The real cost is operational: keeping it patched and, above all, keeping backups you have actually tested restoring.
Can I migrate my existing documents from DocuSign?
Completed envelopes you can export as PDFs and keep. Templates and workflows you rebuild, because there is no import path between these systems. Plan the migration as "new signatures go to the new system" rather than a cutover, and leave the old account open long enough to retrieve archived documents.
What to read next
- Coolify vs Dokploy vs Managed - What self-hosting a platform actually costs
- Keycloak on Docker Compose - Production mode without the footguns
- Fixed-Capacity PaaS: Predictable Cloud Billing for Devs - Why the second self-hosted tool is cheaper than the first