It is safe to send documents via email, but only if you follow certain safety protocols because without extra protection, anyone who handles it along the way can read it. Specifically, sending documents via email safely involves security measures such as encryption, password protection, two-factor authentication, as well as double-checking who receives the file.
You can streamline some of these protection processes using the built-in email service features and online tools for document protection. That said, let’s explore the top six email safety tips and how to put them into practice.
Key Takeaways
- You can send various document types via email, including images (JPG, PNG), documents (PDF, Word, Excel, PowerPoint), and compressed archives (ZIP, RAR)
- Certain file types like HTML or XML may pose security risks, while executables such as .exe files are often blocked.
- Sending documents via email carries risks such as interception, phishing, spoofing, and exposure through unencrypted attachments, all of which can lead to data theft or malware infections.
- To enhance safety, encrypt attachments or password-protect PDFs before sending them, ensuring unauthorized users cannot open your files.
- Send the password separately, by phone, text message, or a messaging app, and never in the same email as the file.
- Use secure sharing alternatives, such as cloud-based links or trackable file-sharing platforms, to monitor access and reduce risks tied to email attachments.
- Always verify recipient addresses and enable two-factor authentication on your email account to prevent unauthorized access and accidental sharing of sensitive information.
What Types of Documents Can You Send via Email?
You can send various types of documents via email, including text, images, and compressed files. For instance, you can share images in standard digital formats, either as an attachment or in the email body, in a bundle, or individually.
Text documents are the most common file type shared via email. You can send PDF, Word, Excel, PowerPoint, and many other document versions using this service. Also, email services allow you to share archived files in the most well-known formats, such as ZIP. However, be careful with archives from unknown senders, though, as they are a common way to hide malware.
Additionally, there are other sorts of supported documents, but users rarely send them due to safety concerns. These include HTML and XML files, as well as CSV, ICS, and VCF ones. Email providers block risky file types, such as executables (.exe) and some scripts, and most limit attachments to 20–25 MB.
Is Email Encrypted by Default?
Only partly. Most major email providers use Transport Layer Security (TLS) to encrypt messages as they move between mail servers, but it works only when both servers support it, and it protects the message only in transit. Once the email reaches a mailbox, the message and its attachments are usually stored in readable form, so anyone with access to the sender’s or recipient’s account can open them.
End-to-end encryption, such as S/MIME or PGP, keeps a message unreadable to everyone except the sender and recipient, but both sides have to set it up. That is why most people rely on simpler options: password-protecting or encrypting the file itself, or using the encryption built into their email service.
3 Common Risks of Sending Documents via Email
Specific risks, such as email interceptions, phishing, spoofing, or using unsecured attachments, can impact safety when sending documents via email.
Let’s take a closer look at these potential threats:
#1. Email Interception
Email interception is a common way people face a data breach. This process can occur in the initial (sending) phase, final (receiving) stage, or in between. For instance, two people may want to use email as a file-sharing service.
Before one of them sends a document, they agree on a password for protection by email, in the same inbox as the file. A third party intercepts this conversation and gets the file and the password before the recipient. This individual sends a random file to the recipient while using the initial document and password to steal information. That is why the password should always travel through a different channel than the file, such as a phone call or a text message.
#2. Phishing and Spoofed Recipients
Phishing attempts are fraudulent activities where the attacker sends messages that falsely appear to be from legitimate sources. For senders, the danger is twofold: you may be tricked into emailing a sensitive document to an attacker, or you may open a malicious attachment that compromises the account you send from.
If you receive a suspicious file or message asking you for money, your bank account, or other personal information, you should double-check the sender’s email. If the sender claims to be a member of a company or organization, we recommend examining the official websites and contacts of the given institution.
Attackers often register a lookalike address (for example, one with a swapped or extra letter), which looks similar to a company’s official address but is not the same. Also, you must not open unexpected attachments, especially .exe files, as these can lead to ransomware or data theft. Some PDFs can also carry viruses.
Moreover, spoofing is a similar practice where someone can forge the sender’s name and address and make it look as if it came from a different sender. They do so to gain the receiver’s trust and eventually get sensitive information. The same trick can be used against you as a sender: a request that appears to come from a colleague, client, or vendor, asking you to send documents to a new address, may actually come from an attacker, so confirm it through another channel first.
You should be cautious on such occasions, see if you expect such an email from someone, and thoroughly examine the sender’s information and email content to avoid repercussions.
#3. Unencrypted Attachments
If you do not use the built-in email encryption that some services provide, you should encrypt attachments yourself. The reason why sending unencrypted attachments is risky is that an interceptor or someone using the receiver’s device can access them.
Precisely, encryption ensures secure file sharing by scrambling the content of your file, making it useless for anyone who accesses it without the decryption key. So, if anyone intercepts such a document or tries to open it on the receiver’s device, they won’t be able to see or change anything.
6 Ways to Send Documents via Email Safely
To make sending documents via email safe, you should focus on file security, transfer safety protocols, and small details like the recipient’s address. As an alternative to sharing attachments, you can even send links in emails.
Due to the immense popularity of PDFs, we discuss how to protect this sort of document, but also share advice on general security measures for sending documents via email safely, which apply equally to Word, Excel, and other files:
#1. Password Protect Your PDF Files
For secure PDF sharing, you can password-protect PDFs and send them via email afterwards. Still, you should choose a reliable tool for this, meaning other users cannot breach your password and can only open it if they have the correct one.
Use a strong password (at least 12 characters, made of several unrelated words) and send it separately. Share it by phone call, text message, or a secure messaging app, so that someone who intercepts or gains access to the email still cannot open the attachment.
While a password stops strangers from opening the file, you can also protect a PDF from copying once the right person has access to it.
#2. Encrypt Your Files or Use Built-In Email Encryption
Encrypting a PDF before sending is closely related to password protection: a password-protected PDF is encrypted, and the password acts as the key. Encryption scrambles the content, so even if someone gets hold of the attachment, they will not be able to read it without the key.
Even if attackers try to copy the unreadable content of your document and paste it somewhere else, hoping to decipher it, this won’t be possible without the correct password or key. Beyond encrypting the file, you can encrypt the whole message with your email service provider:
- Gmail’s confidential mode lets you set an expiration date, revoke access, and require an SMS passcode. It is not end-to-end encryption, so treat it as an extra layer of control rather than your only protection.
- The Encrypt option on Outlook and Microsoft 365 (Microsoft Purview Message Encryption, on supported plans) lets you send a message that only the intended recipients can open.
- Encrypted email providers such as Proton Mail and Tuta encrypt messages end-to-end between their users.
Whichever option you choose, make sure the recipient can open the message before you send anything sensitive.
#3. Remove Hidden Data and Redact Sensitive Details
Documents often carry more information than you can see. Author names, tracked changes, comments, and hidden text or layers can travel with the file and reveal details you never meant to share. Before sending, check the document metadata, accept or delete tracked changes and comments, and remove anything the recipient does not need.
If the recipient only needs part of the information, redact it, so the underlying text is removed instead of merely covered by a black box, which can be undone.
#4. Use Secure File Sharing Links Instead of Attachments
Besides focusing on PDF document security, you can bypass email attachment sharing using links. While cloud computing services can be great secure email alternatives, you don’t need to switch to such platforms completely to send documents safely.
Instead, you can upload your file to a cloud storage or document sharing platform, or create a trackable link and send it via email. These services can track different activities, such as who clicked the links and who accessed the documents, making it easier for you to detect any suspicious activity.
#5. Verify Recipient Emails
Another essential safety measure is checking the recipients’ email addresses before sending emails. This is beneficial because it prevents you from sending confidential documents to an individual they aren’t intended for.
Plus, do not rely on autocomplete or on the fact that you have emailed someone before. Check the full address and domain for lookalike spellings, and if you are sending something sensitive to a new or changed address, confirm it with the recipient by phone or another channel first. A mistyped or autocompleted address is a common way confidential documents end up with the wrong person.
Many email services also offer an undo-send or delayed-send option, which gives you a few seconds to catch a mistake. When you email several people at once, use BCC instead of CC to keep their addresses private.
#6. Enable Two-factor Authentication on Your Email
Using two-factor or multi-factor authentication on your email can help you secure access to your account. Sometimes, even if you protect your files for email sharing, anyone accessing your email address may also sign into your other accounts (e.g., file storage drive or document sharing profiles).
As a result, they may get the unprotected version of your files and tamper with them or use the sensitive data for illegal actions. However, with this layer of security, you will receive an additional code from an authenticator app, a security key, or, as a weaker option, via SMS or email during the login process, which makes signing in without further verification impossible.
Which Way of Sending Documents via Email Is Safest?
The right method depends on how sensitive the document is. Use this table to compare your options:
Method | Security level | Best for |
|---|---|---|
Plain attachment | Low | Non-sensitive files only; anyone with access to the message can open it |
Password-protected or encrypted file | Good | Everyday sensitive documents; the recipient needs the password, sent separately |
Built-in email encryption (Gmail confidential mode, Microsoft 365 encryption) | Good, varies by provider | Added control such as expiry and access revocation; Gmail confidential mode is not end-to-end encrypted |
End-to-end encryption (S/MIME, PGP, encrypted email providers) | Highest | Regulated or highly sensitive data; both sides need certificates, keys, or the same service |
Secure sharing link | Good to high, depending on settings | Large files and tracking access; set expiry and restrict who can open it |
For most everyday documents, a password-protected file with the password sent separately is enough. For highly sensitive records, combine it with a secure link or end-to-end encryption.
Final Thoughts
So, is it safe to send documents via email? Yes, as long as you do not rely on email alone. Standard email protects messages only in transit, so the safest approach is to protect the file itself: use a strong password or encryption, send the password through a separate channel, remove hidden data, and double-check the recipient before you hit send.
For highly sensitive files, a secure sharing link is often a better choice than an attachment, and two-factor authentication keeps your own account from becoming the weak link. Put these habits together and emailing documents becomes a low-risk routine rather than a gamble. When you are ready to lock a file before sending, pdf.net lets you do it in your browser in a few clicks.
Is It Safe to Send Documents via Email? FAQs
#1. What information should not be sent via email?
Personal data such as IDs, SSNs, licenses, sensitive forms, certificates, passwords, and bank account numbers should not be sent via email if you can avoid it. We recommend using maximum file protection if sharing documents via email is your only option: protect the file with a strong password, send the password separately, and delete the message afterward. For the most sensitive data, use a secure sharing link instead.
#2. Can I use email for sending financial or personal information?
Yes, you can use email for sending financial or personal information. However, it is important to share such data in documents that you must protect with a password or encryption. Send the password through a separate channel and confirm the recipient’s address first.
#3. How does pdf.net help with secure document sharing?
pdf.net helps secure document sharing by offering password protection and encryption tools, so your file stays unreadable without the correct password. Also, you can share a PDF through a secure link.