Document signing for small offices on Microsoft 365
Get proposals and contracts signed today.
Upload the PDF or Word file, mark where people sign and send, with the Microsoft 365 you already use. The email goes out from your own address, so clients recognize it. Signers confirm their email with a short code and sign in the browser, no account needed. Everyone gets the signed PDF, sealed so that any later change shows.
Free plan: 100 documents a month. No card, no new logins for you or your signers. Works with any Microsoft 365 business account.
Please sign: Statement of work, website relaunch
Sara Mitchell
sara@harborstudio.com
Hi Daniel,
Here is the statement of work for the website relaunch, as discussed. Signing takes about a minute, and you do not need an account.
Sara
Statement-of-work-Northwind-relaunch.pdf
Signed by 2 of 2
Completed Oct 22, 2026
Seal intact. This document has not changed since it was completed.
How it works
From Word file to signed PDF in four screens
Nothing to install and no new login for you. Your clients, freelancers and new hires need no account at all.
- 1
Upload, mark where people sign, send
Add the PDF or Word file, or start from a template such as your standard NDA. Drag signature, date, text and checkbox fields onto the pages, add the people who need to sign, set reminders and a deadline, then send.
SignatureDRSignaturePNDateDateFieldsSignatureInitialsDate signedTextCheckboxOptionsOrderOne by oneRemindEvery 3 daysDeadline14 days - 2
The email comes from your own address
Most signing tools send from their own servers and domain and show your name on top. SimpleSign365 sends from your own Microsoft 365 mailbox instead: your address, your domain, and a copy in your Sent Items. You allow it once, with your Microsoft sign-in.
- 3
Signers confirm their email, then sign
Each signer opens their own link, gets a short code at their email address and types it in. No account, no app, no password, and it works on a phone. They type or draw their signature, fill in their fields, or decline with a reason.
Confirm your emailWe sent a 6-digit code to daniel.reyes@northwindtraders.com.
482917ContinueResend codeDaniel ReyesSignatureOct 22, 2026Daniel ReyesI agree to sign this document electronically.DeclineSign document - 4
Everyone gets the signed PDF
When the last person has signed, SimpleSign365 adds a page with the signing history (who signed, and when) and puts a digital seal on the PDF. Everyone gets it by email, and anyone holding the file can check it at simplesign365.com/verify. If there is ever a dispute, you have the proof.
What you get
What a small office needs, and not much more
Built for agencies, consultancies and other small offices that already run on Microsoft 365 and want signing to fit in, not stand out.
Sent from your own mailbox
Signing emails and reminders go out from your own Microsoft 365 address and domain, not from a signing service. Replies come back to you.
Templates from Word or PDF
Save a file with the fields already in place. Your NDA, freelancer agreement or engagement letter takes seconds the next time.
Reminders, deadlines, decline and cancel
Set reminders and a deadline for each document and stop chasing people by hand. Signers can decline, and you can cancel at any time.
Signers need no account
Each signer gets their own link and a short code by email. No app, no password, and it works on a phone.
Signed PDF with a seal
The signed PDF gets a page with the signing history and a digital seal. If anyone changes the file afterward, the seal shows it.
For developers
Send documents from your own software and get the signed PDF back automatically. Read the developer page
Security and storage
Plain facts about where your documents live
SimpleSign365 runs on Microsoft Azure. You choose whether your documents are stored in the EU or in the US, and they stay there, along with the signing history.
Read the security pageThe seal
The seal is SimpleSign365's, applied on behalf of your office with the date and time; it is not a personal certificate of each signer. If anyone changes the file afterward, the seal shows it.
Anyone can check a document
Drop a signed PDF on simplesign365.com/verify and it tells you whether the file is unchanged, who signed it, and when. No account and nothing to install.
Stored in the EU or the US, you choose
Your office picks the EU or the US once, when it signs up. All its documents and signing history stay there.
For your IT provider
Three facts they will want: you sign in with Microsoft, so there are no new passwords. SimpleSign365 asks for one mail permission, to send the signing emails you start as you, and you can remove it any time in your Microsoft account. Documents are stored in the EU or the US, your choice.
Pricing
One flat price for the whole office
Pick the plan for the number of people who send. Everyone who signs (clients, freelancers, new hires) pays nothing. The same number in USD and EUR.
Documents are shared across the office, app and API together. Need more? Move to a larger plan. Compare all plans
If you run the office
Three things owners usually ask
What does it cost?
$6 a month for one person who sends, $15 for up to 3, one flat price for the office. Clients and everyone else who only signs pay nothing. Start free with 100 documents a month.
Do we need IT for this?
Usually not. The person who sends signs in with Microsoft and allows the mail permission once. If your Microsoft 365 setup requires an admin to approve it, your IT provider gets a short page to read.
Does it look professional?
The email comes from your colleague's own address, with their name, so clients recognize it. From Solo up there is no SimpleSign365 note, and your logo is on the signing page and in the emails.
FAQ
Questions, answered
Still unsure? The free plan needs nothing but a Microsoft sign-in.
Do signers need an account?
No. Each signer gets their own link and a short code by email. They type in the code and sign in the browser, on any device. Only the person sending signs in with Microsoft.
Is an electronic signature legally valid?
For most everyday business agreements, yes. In the EU, a simple electronic signature with the seal and signing history is valid under the eIDAS rules for anything the law does not require in written form or with a qualified signature (in Germany, for example, leases over one year, fixed-term employment contracts and terminations). In the US, the ESIGN Act and UETA treat it like a signature on paper for most business agreements, with exceptions for documents that have special identity rules, such as IRS e-file authorizations. When in doubt, ask your lawyer.
Where do the signing emails come from?
From your own Microsoft 365 mailbox, with your real work address, and a copy lands in your Sent Items. On the Free plan the email carries a short SimpleSign365 note; paid plans remove it. On paid plans, if your mailbox is unavailable, the email goes out from a SimpleSign365 address instead, with your logo.
Why does it need permission to send email as me?
That is how the email comes from your address. SimpleSign365 only sends the signing emails and reminders you start; it does not read your mail. You allow it once when you sign in with Microsoft, and you can remove the permission at any time in your Microsoft account. In some Microsoft 365 setups an admin has to approve it; the notes for IT providers explain what to click.
Do I need a Microsoft 365 business subscription?
Yes. You sign in with your Microsoft work account, the one you already use for email. Any Microsoft 365 business subscription that includes a mailbox works. Personal Microsoft accounts and Google Workspace are not supported.
We already pay for DocuSign or Adobe Sign. Why switch?
Keep it if you rely on its advanced features. If you send a few proposals, agreements and NDAs a month and mostly want them signed quickly, SimpleSign365 costs less, the email comes from your own address instead of a signing service, and there is nothing new for clients to learn. The free plan is an easy way to compare.
Where is my data stored?
Where you choose: in the EU or in the US. Documents and signing history stay there. Paid plans keep signed documents until you delete them; the Free plan stores no documents at all.
What does the seal prove?
That the PDF has not changed since it was signed, and when that was. For each signer, the signing history records the confirmed email address, name, time and the wording they agreed to. These are simple electronic signatures with a seal on top, not "qualified" or "advanced" signatures in the EU sense. The seal is SimpleSign365's own for now, not issued by an outside authority, so Adobe Reader may say "identity not verified". Use simplesign365.com/verify to check a file instead.
Send your next proposal for signature today
Start with the free plan: 100 documents a month, sent from your own mailbox, with a seal anyone can check. No card, no new logins, nothing to install.