How PactaHQ works

Start from New Document, upload a PDF of up to 20 MB, and add the people who need to sign. Each recipient gets a name, an email address and a role: a signer fills in fields, a viewer only receives a copy.

Then place the fields. Pick a type from the panel and click the page where it belongs. Fields are coloured by recipient, so it is obvious at a glance who is being asked for what. Seven types are available:

• Signature
• Initials
• Text
• Date
• Checkbox
• Name
• Email

Choose whether people sign one at a time, where each signer is emailed only once the previous one has finished, or all at once, where everyone can sign straight away. One at a time is right when a countersignature depends on the first signature already being there.

Signers do not create an account and never see a password. They open the link from their email, confirm a one-time code sent to the same address, and sign in the browser — drawing with a finger or a mouse, or typing a name and choosing a style.

The code matters more than it looks. A link on its own only proves that somebody had the link, which is not the same as proving who signed. Entering a code delivered to the recipient’s own address ties the signature to that address, and the time of that check is written into the certificate.

Every event on a document is recorded: created, sent, opened, verified, signed, completed, expired, voided, deleted. Each entry carries the time in UTC, the IP address and browser it came from, and who did it.

The entries are chained. Each one includes a SHA-256 hash of the entry before it, so the trail can only be extended, not quietly rewritten — removing or editing an event breaks every hash after it, and the document page will say so rather than show a tidy history that is not true.

When the last signer finishes, PactaHQ writes the signatures into the PDF, attaches a certificate of completion, and signs the finished file with an Ed25519 key. The certificate lists each signer, the address their code went to, when they verified, when they signed, and the SHA-256 hash of the original upload.

This is tamper evident, not tamper proof. Nobody can stop a person editing a PDF they hold. What the seal does is make an edit detectable: the signature stops matching, and anyone can check that without asking us, because the evidence travels inside the file rather than living in our database.

That is the practical difference in a dispute. A signing service that keeps the proof on its own servers is proof you have to request, from a company that has to still exist. A sealed PDF is proof you already hold.

A document can carry a reminder cycle and an expiry date. Anyone who has not signed is emailed again on the schedule you set, and on the expiry date the document closes and its links stop working — which matters, because a signing link that works forever is a signing link that works for whoever forwards it.

Reminders and expiry are part of the paid plans. On Free the document stays open and the link stays valid until everyone has signed; you chase people yourself.

Choose Find fields for me in the editor and PactaHQ reads the document and places fields where it asks to be filled in. It recognises a label followed by a blank, whether the blank is typed as underscores or drawn as a line, and it reads the caption printed under a signature rule to tell a signature from a date. Labels can name the thing wanted (“Date”, “Printed Name”), name the party (“Client”, “Tenant”), or ask in a sentence (“Sign here to confirm…”).

It is deliberately cautious. A document written as unbroken prose, with nothing marking where anyone should write, will find nothing — and that is the correct answer rather than a failure. Everything it places is a suggestion you can move, retype or delete, and every field starts assigned to the recipient selected at the time.

A scanned document has no text to read, so the button offers to read the scan instead. That runs character recognition in your browser, which takes a few seconds a page and is less certain than reading a text layer. Check what it places before sending.

Finding fields is part of the paid plans.

A document you send repeatedly can be kept as a template, holding its fields and its signer roles so you never place the same fields twice. Starting from one asks only for the names and addresses this time round. Templates are part of the paid plans.

Build one either way round. Choose New Template on the Templates page and start from the PDF, or prepare a document as usual and choose Save as Template in the editor.

A template can be changed after it is made. Choose Edit and it opens in the same editor a document does, where you can move fields, rename roles, change the routing and set the default message. The template keeps its identity through an edit: documents already sent from it stay linked to it, and its use count is not reset by moving a signature box.

A template names roles rather than people. “Client” or “Tenant” describes who signs, and the actual name and email address are filled in each time you send it, which is why nothing personal is stored on the template itself.

Deleting removes the file and every field on it. There is no undo, and the deletion itself is recorded — the audit trail keeps a note that a document existed and was deleted, because a record that can be made to look like it never happened is not a record.

What is limited is automation, never volume or proof. Unlimited documents, unlimited signers, the full audit trail and the sealed PDF are on every plan including Free.

• Free, free. Everything above, placing fields by hand. No field detection, no templates, no reminders, and our name on the signing page.
• Solo Pro, $4.99 a month or $49 a year. Automatic field detection, templates, reminders and expiry, and your own branding. One person.
• Business, $11.99 a month or $119 a year. Everything in Solo Pro for your whole team, at one price rather than per seat.

See pricing for the full comparison.

PactaHQ is built for electronic signatures in the United States, under the ESIGN Act (15 U.S.C. 7001) and UETA. Those laws ask that signers intend to sign, consent to doing it electronically, and that a record of the transaction is retained and reproducible — which is what the verification step, the audit trail and the sealed PDF are for.

It is not a qualified electronic signature under eIDAS, and we do not claim EU or UK legal equivalence. If you need a qualified signature, you need a qualified trust service provider, which we are not.

Write to support@pactahq.com and a person will answer. See also the privacy policy for what is stored and for how long, and the terms.