Why proper list hygiene and recipient collection matter?
List hygiene refers to the process of maintaining an email recipient list to ensure it remains clean and qualified. The primary objectives of good list hygiene are to prevent delivery issues and optimize the results of marketing campaigns.
Maintaining a correctly managed recipient base reduces the risk of:
Harming your sender reputation, which can result in deliverability issues or blocks from inbox providers.
Receiving negative feedback from recipients, who may not expect or want to receive your emails anymore (e.g. bounces, unsubscribes, spam complaints).
Facing legal issues due to poor consent collection and data deletion processes.
In this article, we will go through:
Solutions to clean your current recipients base
Solutions to keep your recipients base clean
Approaches to qualify your recipients list
Clean your recipients base
Identify risky recipients
Exclude the following types of email addresses from your subscriber base:
Accept-all email addresses: These email addresses may not exist per se, but their domain is set up to accept every email sent to it. While they don't represent a high risk, they tend to reduce engagement generated by your campaigns since no one receives your emails and damage in the long.
Disposable email addresses: Disposable email addresses are used temporarily by users to sign up and access a resource/service. They have no value by themselves and may cause hard bounces.
Role-based email addresses: These are generic email addresses created by companies for specific missions or internal services (e.g., sales@domain.com, support@domain.com, etc). Role-based addresses usually generate multiple unsubscribes for the same email address, spam complaints, in addition to generating very low engagement.
Email addresses with typo domains: These are email addresses mistyped by legitimate subscribers (e.g., gamil.com instead of gmail.com, etc). This causes two issues:
Your users cannot receive emails related to your service and newsletters.
These addresses will bounce or can be spam traps, causing email reputation issues.
By excluding these risky email addresses from your subscriber base, you can maintain a healthy sender reputation and improve overall campaign performance.
Clean the recipients base you want to migrate
In order to check the quality of your current recipients base, you can:
Remove hard bounces: If it's not the case yet, remove all the recipients that returned a hard bounce in the past. See if your current provider can provide a "suppression list" that will match your need.
Remove inactive recipients: Remove 6 months+ recipients that never opened a single email.
Use lists of throwable domains: Allows you to exclude domains known to be unreachable, mistyped or with no added value. Here is an example.
Use dedicated list validation tools: Many options exist today to check the quality of your recipients base (e.g. Validity, Kickbox, Mailnjoy, etc).
Keep your recipients base clean
Improve your subscription form
As a sender, you can implement several improvements to your sign-up/subscription form to limit the risk of collecting invalid or risky email addresses.
Double email address confirmation form
Ask users to re-type their email address without allowing copy-paste or double-check the email address they just typed.
Email domain completion
You can also reduce the risk of errors by helping your users to type the rest of their email address, as follows:
Verify the validity of the email addresses
Users should only be allowed to use valid addresses, not longer than 256 characters. They must match the following pattern:
^[^\r\n\t@]+@[A-z0-9\-\.]+\.[A-z0-9]+$
Also, as explained here you should not allow users to use an email domain that is tied to:
Known typo domains
Disposable email addresses
Role-based addresses
Third-party solutions like Validity, Kickbox and others provide APIs allowing you to check the validity of an email addresses. This comes in handy to decide if you should accept or an email address.
Promote single sign-on options
Offer users the option to sign up using single sign-on options (e.g., Google, Apple, Facebook, etc) to reduce significantly the risk of collecting invalid or incorrect email addresses. We recommend displaying the single sign-on option first and only offering the "type an email address" option as a secondary choice.
By promoting single sign-on options, you can improve the overall quality of your email list and maintain a healthy sender reputation.
Implement a double opt-in
Double opt-in (DOI) is a robust anti-spam technique used in email marketing campaigns to ensure that users validate their subscription to receive emails from your brand.
After users sign up or subscribe to a newsletter, send them a confirmation email asking them to "opt-in" again by clicking a link. Once they have confirmed the subscription, you can store the consent and add them to your subscribers' base.
Double opt-in is legally required in some countries and strongly recommended for all users. This technique offers numerous benefits, including:
Collecting only valid email addresses , reducing the hard bounce rate.
Ensuring that users who subscribe really want to subscribe and increase engagement rates.
Providing an additional layer of proof that your contacts gave consent to inbox providers and authorities.
Protect your subscription form
Subscription bombing or subscription spamming is a significant risk for most senders who have an exposed subscription/sign-up form on their website and apps. Subscription bombing is a malicious practice where attackers subscribe large amounts of email addresses (real or fake) to a list, often using automated scripts.
This can be done by collecting email addresses without permission, which can lead to:
Bounced emails: If the email addresses are no longer active, this may cause a sudden increase in bounces.
Spam traps: Some email addresses may be spam traps, leading to reputation issues and potentially harming your sender reputation.
Poor engagement: Subscribers added to your list will likely not react to your emails, reducing the engagement rate of your campaigns.
Spam complaints: Your new "subscribers" will likely file massive amounts of spam complaints after receiving their first emails.
Subscription bombing can significantly harm your email marketing efforts and negatively impact your sender reputation. To prevent this, it's essential to:
Add a reCAPTCHA to your form, to limit the risk of getting fake subscribers.
Add fields, invisible to normal users but visible to bots (e.g. additional checkboxes, fields, etc). Bots tend to tick checkboxes and fill in fields, which can prove the email address is not from a legitimate subscriber.
Monitor your subscription form for unusual activity
Keep an eye on your bounce rate and engagement rates
Qualify your recipients base
Inbox providers are increasingly focusing on the quality of a recipient's email address base and engagement metrics. Subscribers are also receiving more and more messages across various channels. In this environment, senders need to reassess their list hygiene strategy to ensure compliance with new constraints.
Adapt your messages and campaigns to your audience
Leads, newsletter subscribers, and your service users didn't share their email address with you for the same reason.
As a consequence, sending the same emails to very different audiences can generate positive engagement for some and irritation for others. In case you have different type of subscribers, attach a subscription source so you can exclude some category of subscribers:
Avoid luring sign ups with free giveaways
We strongly advise against running contests or other strategies to incentivize sign-ups. This approach can have negative consequences, including:
Unengaged subscribers: Many of these subscribers will likely unsubscribe as soon as they can, ignore your content, leave spam complaints, and damage your reputation.
Email validity: Some of these subscribers may use email addresses dedicated to contests only. They won't open your emails or will return an inbox full bounce, wasting your time and resources.
If you still decide to run a contest for sign-ups, make sure to identify these subscribers and onboard them with special communications, such as:
Welcome emails that set expectations
Targeted content that aligns with their interests
Clear instructions on how to interact with your brand
However, we strongly recommend against using contests or other manipulative tactics to grow your email list. Instead, focus on building relationships with genuine subscribers who are genuinely interested in your content and offers.
Sunset inactive subscribers
First, make sure you are exclusively targeting users who are active and expect your emails.
From a technical points of view, this implies to:
Sunset recipients who never opened a single email.
Sunset recipients with recurring inbox full issues, as requested by inbox providers.
Unsubscribe or exclude from your marketing communications recipients who haven't opened your emails or have been inactive for 3 months (e.g. no use whatsoever of your service).
From a technical perspective, this implies:
Sunset recipients who never opened a single email: Remove or deactivate accounts that have never engaged with your emails.
Sunset recipients with recurring inbox full issues: Address and resolve issues with users' inboxes being consistently full, as required by inbox providers to prevent bounces and complaints.
Unsubscribe or exclude inactive users: Remove inactive subscribers who have not interacted with your content or services for a prolonged period (e.g. 3 months of no usage). This ensures that only engaged and active users remain on your email list.
Note: By default, Batch will delete profiles after 13 months of inactivity.
Make it easy to unsubscribe
Make sure subscribers always find a way to unsubscribe to your emails. This is key to avoid getting spam complaints, which is worse than a simple unsubscribe:
All marketing emails must include an unsubscribe link in the footer.
The unsubscribe link must be visible and easy to understand for the recipient.
If in the footer you have a link to a subscription center subscribers must visit to stop receiving certain emails (e.g. different newsletters, etc), also add a link to unsubscribe to all marketing emails.
If you are targeting a less engaged audience, give them a chance to unsubscribe easily from the very beginning of the email to avoid irritating them.
If your email is long and may be clipped by some inbox providers, add the unsubscribe link in the top part of your email too.
Batch will honor the unsubscribe in near real-time. If you handle the unsubscribe on your end, please honor it as soon as possible. Never take more than 24h to apply changes.
Batch will automatically exclude from your marketing communications users who filed a spam complaint.
By default, Batch includes a list-unsubscribe header to marketing emails, allowing recipients to unsubscribe with a single click:
Proactively unsubscribe less engaged subscribers
As a sender, you can be proactive an send an email to your subscribers after 2-3 newsletters without any open. Simply send an email asking them if they are still interested, allowing them to:
Option A: Confirm they want to keep receiving emails
Option B: Unsubscribe with one click
This will be useful to stop loosing engagement on your marketing emails and avoid getting spam complaints.