Mailock® Free

Free secure email

for a safer world

Exchange private information safely

Reply to secure emails you receive from premium users and send 5 encrypted emails to new contacts each month.

Man in office securing email and smiling with a coffee cup

Sending securely

How it works

1. Encrypt

Start a secure email from your desktop email client or your web browser. Set a challenge so only the right people gain access.

Start a secure email with a button in your email client

2. Connect

Recipients click ‘Open’ on the notification delivered to their inbox. They’ll answer your challenge in our browser app, or, if they're trusted, they’ll open and read right away.

Challenge question Mailock UX (1)

3. Engage

Our browser app works just like an email client. Recipients download attachments, compose, and reply. (Their replies can be auto-decrypted to your Outlook inbox.)

Secure read pane in Mailock web app
Start a secure email with a button in your email client
Challenge question Mailock UX (1)
Secure read pane in Mailock web app

Why Mailock?

Email freely without
risking your data

A digital world

In a digital age, it's more important than ever to prioritise online security. Email is a popular mode of communication for personal and professional purposes, but many email providers may not offer adequate protection against cyber threats.

couple at home using tablet

Open to threat

Most email providers lack essential security features, leaving users vulnerable to interception and hacks. By signing up for a secure email provider that offers email encryption and authentication features for free, you can get protected.

woman made an email mistake

Free secure email

No need to switch

your email account

Free secure email on any device

Secure confidential emails and attachments using our Windows Outlook add-in or the Mailock browser app.

  • End-to-end email encryption
  • Q&A recipient authentication
  • Free secure reply for recipients
Receiving an email on phone using mailock (1)

Q&A authentication

Double check your

recipient's identity

Reach the right people, only

Authenticate recipients when they open your emails. Set a question they’ll have to answer correctly for access.

  • Protect personal information
  • Prevent email interception
  • Comply with the GDPR
Mobile challenges Free
Couple reading emails

Protect data

Are your emails confidential? Mailock uses end-to-end encryption to prevent email interception by cyber criminals.


Reduce admin

No need to post a document to get proof-of-delivery. Mailock tells you when your secure emails get opened.


Prevent misfires

Secure messages and attachments with a challenge question so only the intended recipients can gain access.


Save carbon

Why waste paper when you can send documents faster, more efficiently, and more securely with Mailock?


Safe & secure!

Fast - and good to know my details are safe. Easy for me to work out. When I spoke to customer service, they were very helpful.

 James  Mailock user
Man using free secure email on sofa in office


Encrypt emails and attachments at the click of a button

Securely send confidential information by email, for free. Keep your data private.



Secure emails using Windows Outlook or our secure browser app. Click the Mailock icon to get started.


Deliver emails and attachments with end-to-end AES-256 encryption - the NSA standard for classified data.



Email misfires are the top cause of data loss. Set challenges so only the right people can open.



Recipients reply securely for free - empower partners and clients by giving them a safe way to respond.

Download the Mailock
Free Plan Data Sheet

Man in office securing email and smiling with a coffee cup (1) (1)

Get started

Create your account

Our free plan gives you unlimited secure email replies and 5+ sends each month.

Case studies

  Hear from our users

6 min read
Rapport financial strategists
05 05 23

Boosting Security And Engagement At Rapport Financial Strategists

This case study shows how Rapport Financial Strategists improved the security and effectiveness of their client communications using Mailock secure email.

2 min read
Woman speaking to colleague in office about email security
22 02 23

Brearley Law Puts The Protection Of Client Data First With Mailock

According to the most recent ICO statistics, the UK legal industry is responsible for 8% of total data breach incidents reported in the past year.

2 min read
Securing client communications at Stonebridge Financial
21 12 22

Securing Client Communications At Stonebridge Financial

Find out how Stonebridge Financial secured their email communications using Mailock, driving efficiency and engagement with their clients in the process.