How to Sign a Contract from Gmail in 2026
April 14, 2026 · 8 min read
A contract just landed in your Gmail inbox and the sender wants it back signed within the hour. Here is how to go from unopened email to signed-PDF-reply in under 90 seconds, with a full audit trail, no installed app, and no retyping anything.
The Two Scenarios
There are two ways a contract arrives in Gmail:
- As a PDF attachment. The sender attached the PDF and expects you to sign it and email it back.
- As a signing link. The sender used an e-signature tool (SignBolt, DocuSign, etc) and you get a link to click.
The second case is easier — just click the link. This guide focuses on the first case, where you need to take a PDF attachment and return a signed version.
The 60-Second Method
- Open the Gmail email and confirm the sender is who you expect.
- Click the PDF attachment to preview it in Gmail.
- Click the download icon (arrow pointing down) in the top-right of the preview. The PDF saves to your Downloads folder.
- Open signbolt.au/sign in a new tab.
- Drag the downloaded PDF onto the SignBolt page. The PDF uploads and renders.
- Click where your signature goes on the PDF preview. SignBolt places a signature, which you type or draw.
- Repeat for initials or additional signature fields if the contract needs them.
- Click Sign. SignBolt generates the signed PDF with embedded signatures and downloads it to your computer.
- Back in Gmail, click Reply, attach the signed PDF, and hit Send.
Total time: 60-90 seconds on a typical 5-page contract.
The Even Faster Method: Ask for a Signing Link
If you sign contracts from the same sender regularly, ask them to switch from sending PDF attachments to sending SignBolt signing links. Your workflow becomes: click the link in Gmail, sign, done. No download, no upload, no attachment reply. The sender also gets a cleaner audit trail.
Using a Chrome Extension
Chrome extensions exist that add a "Sign in SignBolt" button directly into Gmail's PDF preview. If you sign contracts from Gmail weekly, installing one of these cuts the flow from 60 seconds to 20 seconds. Search the Chrome Web Store for "signbolt gmail" or use the generic Gmail PDF handler.
Signing on Mobile Gmail
The iOS and Android Gmail apps handle PDF attachments slightly differently. On iPhone:
- Tap the PDF attachment in the email.
- Tap the share icon (square with arrow).
- Choose Safari or Chrome.
- In the browser, open signbolt.au/sign.
- Use the iOS Files picker to pick the PDF (which is now in your temporary Files).
- Sign and download.
- Return to Gmail, reply, attach from Files.
On Android the flow is identical with Chrome and Files.
When to Reply vs Return to Sender
After signing, standard practice is to reply-all on the original email thread with the signed PDF attached and a short note: "Signed and returned — see attached." This keeps the thread searchable and makes clear you are returning the same contract.
If the contract is sensitive, reply directly to the sender only (not reply-all) and ask them to confirm receipt.
Security Notes
- Always verify the sender email before signing.
- Verify the signing tool URL (signbolt.au or signbolt.store).
- Do not sign contracts from unknown senders without verification.
- For high-stakes documents, phone the sender on a known number before signing.
- Keep a copy of both the unsigned and signed PDFs in your records.
Related Reading
See how to send a document for signature, how to sign a PDF on Mac, Google Workspace integration.
Frequently Asked Questions
Do I need to download the PDF from Gmail before signing?
No. Gmail has a built-in PDF viewer, but the simplest flow is: click the attachment, choose 'Open with' and pick your e-signature tool if installed, or click the paperclip download once to save to Downloads then upload to SignBolt. The whole round-trip takes 30 seconds. For the cleanest path, install the SignBolt Chrome extension or use 'Open in new tab' on the Gmail preview.
Can Gmail users sign without creating a SignBolt account?
If you are the sender, you need a free SignBolt account (takes 30 seconds with just email and name). If you are the counterparty receiving a signing link from someone else, you do not need an account — you click the link in your Gmail, sign in the browser, done. This is the standard pattern: SignBolt users send requests, anyone with an email address can sign.
How do I know the Gmail sender is legit before signing?
Three checks. First, verify the sender's email address is the one you expect — check the 'from' field carefully (attackers use lookalike domains). Second, hover over the SignBolt signing link and confirm it goes to signbolt.au or signbolt.store (not a lookalike). Third, if the document is high-stakes, call the sender on a known phone number to confirm they sent it. SignBolt emails signing requests from noreply@signbolt.store — that domain is verified in Resend and should match.
Can I sign a contract from the Gmail iPhone app?
Yes. Tap the PDF attachment to preview, tap the share sheet, choose Safari or Chrome, open the PDF in SignBolt. Or, if the sender used SignBolt's send-for-signature, just tap the signing link in the email — it opens in Safari and the signing flow is mobile-optimised. Takes under a minute on 5G.
What if the contract PDF is too large for Gmail's 25MB limit?
Gmail attachments cap at 25MB. Large PDFs (over 100 pages or image-heavy) can exceed this. The sender typically works around by using a Drive link in the Gmail body instead of an attachment. For signing, SignBolt handles PDFs up to 50MB on the free plan — more than enough for standard commercial contracts. If the document is larger, split it or compress images before uploading.
Sign a Gmail attachment in 60 seconds
Free for 3 documents/month. No install, works on any browser, mobile-friendly.
Start Free