In much of the world, the fastest way to reach someone is not email but WhatsApp. A contract emailed on Monday can sit unopened until Thursday; the same document sent as a WhatsApp message is often signed within the hour. This guide shows how to send a document for signature through WhatsApp properly, so you get a real electronic signature and a record of it, not a blurry photo of a page.
The wrong way: a PDF in the chat
The tempting shortcut is to send the PDF as a WhatsApp attachment and ask the other person to "sign and send back". They then have to download it, find an app to sign it, export it and send it back, or print, sign and photograph it. You end up with a picture of a signature, no record of when it was made, and no proof that the page they signed is the page you sent.
The right way: a signing link, shared on WhatsApp
Send the document through an e-signature service, which creates a personal signing link for each signer, and share that link on WhatsApp. The signer taps it, signs in their browser, and the service records every step.
With Salsox it takes four steps:
- Upload the PDF and add the signer. Quick Send places a signature and a date field for each signer automatically; use the editor for anything more specific. Adding the signer's phone number, with country code, lets WhatsApp open straight to their chat.
- Send. The signer gets the usual email invitation as well.
- Open the Share menu beside the signer on the document's page, and choose Send via WhatsApp.
- Add a line of context in WhatsApp before sending: "Hi Kofi, here's the quote we discussed. It takes a minute to sign."
The same menu can send the link by SMS from your own phone, open it in your email app, or copy it to paste anywhere else.
What the signer sees
The link opens in the phone's browser, so nothing needs installing and no account is needed. The signer sees who sent the document, agrees to sign electronically, completes each field with their finger or by typing, and finishes. When everyone has signed, they can download the signed PDF straight away. Our guide to signing documents on your phone shows each screen.
Keeping it secure
A signing link is a key: whoever opens it can sign as the person it was made for. A few rules keep that safe:
- One-to-one chats only. Never post a signing link in a group, even a group of the people who need to sign: each person has their own link.
- Check the number before sending, especially for a new contact.
- If it went to the wrong person, correct the recipient on the document's page. Their old link stops working at once and the right person gets a new one. Our guide to correcting a document after sending covers this.
- Links expire. Set an expiry that suits the document, so an old link cannot be used months later.
WhatsApp's end-to-end encryption means the message travels privately between the two phones, and the signing itself happens over an encrypted connection to the signing service.
Following up on WhatsApp
WhatsApp shows whether your message has been read; the document's page shows whether the link has been opened and signed. Together they tell you exactly where things stand. Salsox also reminds unsigned signers automatically every three days by email, and, on deployments where SMS reminders are enabled, by text message to signers with a phone number.
If someone has read the message but not signed, a short personal follow-up in the same chat usually works: "Any questions about the quote before you sign?" Our guide on what to do when someone won't sign covers the harder cases.
When email is still the better channel
WhatsApp is fastest for individuals, sole traders and anyone who lives on their phone. Email is still better when:
- the signer is in a large organisation that expects contracts by email;
- the document needs a paper trail in a shared inbox;
- you do not have the person's number, or have never messaged them.
You do not have to choose: the email invitation goes out either way, and WhatsApp is an extra nudge where it helps. For wording that works in an email, see how to request an e-signature by email.
What it costs
Sharing a signing link through your own WhatsApp or SMS costs nothing beyond your usual phone plan. Some e-signature providers charge for sending texts themselves; DocuSign, for example, lists SMS delivery as an add-on starting at $0.36 per delivery (checked on its pricing page on 16 October 2026). In Salsox, WhatsApp and SMS sharing is included on every plan, including the free one.
Try it
Create a free account, send a document to yourself, and share the link to your own WhatsApp to see the whole flow. The free plan sends 3 documents a month; the paid plans are on the pricing page.
Frequently asked questions
Can I get a document signed through WhatsApp?
Yes. Send the document through an e-signature service, then share the signer's personal signing link in a WhatsApp chat. They open it, sign in their browser and you both get the signed PDF. Sending a PDF in the chat and asking for a photo of a signature gives much weaker evidence.
Is it safe to send a signing link on WhatsApp?
WhatsApp messages are end-to-end encrypted, so the link travels privately to that person. Send it only in a one-to-one chat, never a group, because the link signs as the person it belongs to.
Does the signer need WhatsApp to sign?
No. WhatsApp only carries the link. The signing happens in the phone's browser, with no app or account needed.
Can I send signing links by SMS instead?
Yes. The same link can go by text message. Some providers charge for SMS delivery; DocuSign lists it as an add-on from $0.36 per delivery. In Salsox, sharing a link by SMS from your own phone is included.