Security

Why sending a document for signature is worth more than emailing a PDF

Emailing a PDF back and forth leaves you with a file and a mailbox. Sending it for signature leaves you with a single finished document, a record of who did what and when, and a seal that makes later changes detectable.

4 min read

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Plenty of agreements get signed by emailing a PDF and hoping for the best. It works, until the day it does not. This page sets out (factually, without giving legal advice) what a proper signature request gives you that an email thread does not.

What the email version actually looks like

You attach the contract. They print it, sign it, photograph it with a phone, and email back a crooked, grey scan. Or they open it in some app, drop a picture of their signature on page 4, and send it back. Or they reply "yes, agreed" and nobody signs anything at all.

Now, what do you have?

A file whose origin you cannot prove.
No record of when they opened it, or whether they read past page 1.
No proof they got the version you sent, rather than one with a changed number.
Evidence scattered across an inbox that will be migrated, cleaned out, or lost with the laptop.
And if there are four signers, four inconsistent files and a threading problem.

What a signature request gives you instead

One finished document. Everyone's fields and signatures on one PDF, not four versions to reconcile.

A record of the process. The certificate of completion lists every person, their role, when they opened it, when they signed, from which IP address and on what kind of device, and how many fields they filled, plus a timeline of every event, including reminders and any handovers.

A fixed starting point. The original document's fingerprint is recorded, so "that's not the version I was sent" is answerable.

A seal on the result. When the timestamp service can be reached, the finished file is sealed with a trusted timestamp. Any later change shows up in any PDF signature checker. You can test it yourself in Verify PDF Signature.

A clear process. Required fields must be filled. Signers confirm they agree to sign electronically before signing. Nobody can accidentally miss page 6.

Control while it is out. You can see where it has got to, remind people, resend a link, or cancel.

The everyday version

Two ways to deliver a parcel.

Email: leave it on the doorstep and hope. Probably fine. No record if it is not.
Signature request: tracked delivery. Time of dispatch, time of arrival, who signed for it, from where.

Same parcel. Utterly different position if something goes wrong.

Where this matters most

Rental agreements. Deposits, dates and conditions, argued about a year later.
Offer letters and contracts of employment. Start dates, salary, terms.
Supplier and client agreements. Amounts, delivery dates, scope.
Consent and policy acknowledgements, where you may need to show a particular person acknowledged a particular version.

For a leave request or an internal note, an email is fine. Use the heavier tool where a dispute would actually cost something.

Being honest about what it is

Two things the tool itself states, and this page will not dress up:

The signatures made through a request are electronic signatures made in the signer's browser. They are not certificate-based digital signatures belonging to each signer. If each signer must hold their own certificate, that is the Digital Signature tool.
Whether an electronic signature is sufficient for a particular document depends on the law that applies to it, and it differs by country and by document type. Some documents (certain wills, deeds and property transfers) have special requirements in many places.

Where to check the rules

We have separate guides for that, written country by country. Start with the one for where you are:

And for particular document types: can you e-sign a lease or rental agreement, can an employment contract be signed electronically, can you sign a will electronically, and digital vs electronic signature: which does the law require.

The practical summary

Nothing here makes a document legally binding that would not otherwise be. What a signature request does is give you a single finished file, a written record of how it was signed, and a seal that makes later changes visible: which is exactly what you wish you had on the rare day someone disagrees.

Common questions

Why not just email a PDF to be signed?

You can, and for low-stakes documents it is fine. What you lose is the record: when it was opened, by whom, from where, which version they saw, and a seal showing the finished file has not changed since.

Does sending through an e-signature tool make a document legally binding?

It does not change the law. It provides a record of the signing and a sealed final document. Whether an electronic signature is sufficient depends on the document and the country, so check the rules that apply.

Is a print-sign-scan copy as good?

It gives you a picture of a signature and nothing else. No record of when or by whom, and no way to show the document was not altered. It is the weakest of the options.

Are these signatures the same as certificate-based digital signatures?

No. Signatures made through a request are electronic signatures made in the signer's browser. If each signer needs their own certificate, use the Digital Signature tool instead.

What stops someone changing the document after everyone has signed?

The finished file is sealed with a trusted timestamp when the service can be reached. Any change afterwards shows as a broken seal in any PDF signature checker.

Which documents should not be signed this way?

Some document types (certain wills, deeds and property transfers among them) have special requirements in many countries. Check the rules for your country and document type before relying on an electronic signature.