Security you can trust

Mailflow is like a layer on top of your Google account that enhances your Gmail app. We know that email is the heart of your business, and it's our top priority to make sure that nobody gets unwanted access to sensitive details or information. On this page, you'll find an overview of how we protect your emails and data.

The short version:

  • Mailflow uses Google OAuth for sign-in.
  • Your emails are never processed without your permission.
  • We don't store your emails.
  • All data is stored on Google's servers.
  • All data is encrypted at rest and in transit.
  • All data is backed up 24/7.
  • Employee access is limited and audited.
  • We're conducting external security audits annually.
  • You will be notified if any incidents were to happen.
  • We run a vulnerability disclosure program.

Mailflow uses Google OAuth for sign-in

Since Mailflow requires a Google account to work, we use Google's own login solution. This means that we can never access or store your password when you log in. It also means that you get the same industry-leading security when logging into Mailflow as with your Google account.

We strongly advise you to enable two-factor authentication for your Google account if you have not done so already.

Your emails are never processed without your permission

We never process any emails without you giving explicit permission by using one of our features. By processing of emails, we mean doing things like saving recipients, email subjects, or generating thumbnails of attachments to present them back to you. If you use our email sharing feature, we also need to process the email thread to sync it with the people you shared it with.

We don't store your emails

Mailflow never stores your email unless it's temporarily needed to sync a shared thread with another person. Once the syncing is completed, the email is deleted from our system. The emails are stored in your Gmail mailbox and fetched via the Gmail API on request. This means that even if someone were to break into our database, they would not manage to read any of your emails because they are not there.

Your data is stored on Google's servers

All data is stored and processed using Google Cloud Platform (GCP), which is Google's own infrastructure. Geographically, our data are stored in Google's data center in Belgium, within the EU.

The great benefit of using Google Cloud Platform is that we get the same security policies, procedures, and infrastructure as Gmail itself or other Google products. The system gives us a failsafe and failover system. Meaning that if any server instance were to go down, another will take its place and ensure we don't get any downtime. Despite that, our systems are still monitored 24/7. If any downtime or incident were to happen, we'd be notified instantly so that we can fix the issue.

All data is encrypted in-transit and at-rest

In-transit encryption means that all your data is encrypted using industry-standard TLS encryption when sending data from the Mailflow Chrome Extension to our servers.

At-rest encryption means that all of our databases and other storages have their files encrypted when backed up or idle. If someone could get ahold of a copy of our database, it would be useless because they don't have the key to decrypt it.

The data in Google Cloud Platform is also broken into subfile chunks for storage. Each chunk is encrypted with an individual encryption key. You can read more about how Google Cloud Platform handles encryption on their website.

All data is backed up 24/7

Your data is backed up every 24 hours at seven days a week as a minimum, and the backups are stored for seven days. If some incident were to happen, we'd always be able to restore a copy.

Employee access is limited and audited

We never access or view your data unless we need to resolve an issue or improve your service.

Only the people who need access to improve or operate the system have access. That access is limited as much as possible to an as-need basis.

If any of our personnel were to wrongly access user data through our system, it would be treated as a serious matter requiring investigation and appropriate penalties, ranging from termination to prosecution.

External security audits

How can you be sure that we're doing a good job keeping your data secure? You could take our word for it, but we completely understand if you didn't. That's why Mailflow undergoes Google's OAuth API review process every year, and an external security firm performs the review. The purpose is to make sure that we're handling data security and potential incidents in a safe way.

You will be notified if any incidents were to happen

Suppose a serious downtime incident were to occur, we will notify you via email or an appropriate channel.

Any planned downtime to perform system upgrades or maintenance will be notified well in advance, either via email, Twitter on our blog.

If a security breach were to occur, we will notify the affected users about the implications and severity of the breach.

Vulnerability disclosure program

No matter how much effort one puts into security, there will always be a risk of vulnerabilities in any system. To minimize that risk in our system, we run a vulnerability disclosure program to ensure that potential problems are resolved quickly and safely.

If you have found a security flaw in our product, we would be grateful to hear from you. Visit our vulnerability disclosure program if you have found a flaw and want to notify us.