What defines an inactive user?

An inactive user is typically defined by a lack of engagement with your emails or platform over a set period. This can include not opening emails, not clicking links, or not logging into an associated account. While the exact duration varies, any user inactive for four or more years is considered highly dormant and risky.

How does sending to inactive users affect deliverability?

Sending to inactive users significantly harms your email deliverability. It leads to higher bounce rates, increased spam complaints, and a greater chance of hitting spam traps. These negative signals alert ISPs that your mail is unwanted, degrading your sender reputation and causing your emails to land in spam folders or be blocked.

Are there any scenarios where emailing very old inactive lists is acceptable?

It is generally not recommended due to the high risks of damaging your sender reputation. If absolutely necessary, a highly cautious strategy involves segmenting the list, using email validation , sending in very small batches, and quickly removing any contacts who do not re-engage. Always prioritize list hygiene over size.

What is a spam trap and why is it dangerous?

A spam trap is an email address used by ISPs or anti-spam organizations to identify senders with poor list hygiene. Hitting a spam trap can immediately lead to your IP or domain being placed on a blocklist (or blacklist), resulting in severe deliverability issues for all your email campaigns. There are different kinds of these traps, some from old addresses.

How often should I clean my email list?

The frequency of list cleaning depends on your sending volume and list churn, but a general best practice is to remove unengaged subscribers who haven't opened or clicked in 6-12 months. For highly inactive segments, a much shorter timeframe (e.g., 3 months of no engagement) might be appropriate before removal or aggressive re-engagement attempts.

Is it bad to email users inactive for 4+ years? - Sender reputation - Email deliverability - Knowledge base

The idea of emailing users who have been inactive for four or more years often sparks debate among email marketers and deliverability experts. While the desire to reactivate a large, seemingly dormant segment of your audience is understandable, the reality is that such a practice carries significant risks for your email program.

A common misconception is that these accounts are simply abandoned, and therefore, poses no harm. However, the primary concern isn't necessarily that mailboxes are universally abandoned after a specific timeframe, but rather that the individuals behind those addresses have completely disengaged from your brand, or worse, the email addresses have been repurposed as spam traps.

Ignoring this long-term inactivity can lead to severe consequences for your sender reputation and overall email deliverability. It's crucial to understand the implications before attempting to re-engage such an aged list.

The perils of emailing aged inactive lists

Emailing addresses that haven't shown any engagement in four or more years is akin to sending emails to a purchased list. The recipients have likely forgotten they ever subscribed to your communications, leading to high unsubscribe rates and, critically, an increased likelihood of spam complaints.

These negative engagement signals tell Internet Service Providers (ISPs) that your emails are unwanted, severely damaging your sender reputation. A tarnished reputation can result in your emails being directed to the spam folder, or even being outright blocked, impacting deliverability even for your active subscribers. In the worst-case scenario, your domain could end up on an email blocklist (or blacklist), making it extremely difficult to reach any inbox.

The greatest threat, however, comes from spam traps. These are email addresses specifically designed to catch senders who use poor list hygiene. There are different types of spam traps, including recycled spam traps (old, abandoned addresses repurposed by ISPs) and pristine spam traps (addresses that have never been used for legitimate email). Hitting even a few spam traps can quickly land your IP or domain on a blocklist, causing significant deliverability issues.

The risks of emailing inactive users

Spam complaints: Recipients who don't recognize you are prone to mark your emails as spam, signaling to ISPs that your content is unwanted.
Spam traps: Old, dormant addresses can become spam traps, which are traps that severely harm your sender reputation if hit.
Reduced deliverability: ISPs will send more of your emails to the spam folder or block them entirely, even for active subscribers.
Blocklisting: Your domain or IP address might get placed on a public or private blocklist (or blacklist), making it nearly impossible to reach the inbox.
Wasted resources: Sending emails to inactive contacts costs money without yielding positive results.

Why inboxes go dark

It's important to distinguish between an email address that has truly been abandoned and one where the user simply hasn't engaged with your emails. Many people retain email addresses for decades, especially those from major providers.

However, email providers do have policies on inactive accounts. For instance, Google's inactive account policy states that accounts inactive for at least two years may be deleted. Microsoft has a similar policy. If an account is deleted, the address may then be recycled into a spam trap.

Even if the account isn't deleted, a user who hasn't opened your emails in years might simply have them going to their spam folder without realizing it, or they may be deleting them without opening. The lack of engagement still sends negative signals, irrespective of whether the inbox is truly abandoned or not.

Furthermore, regulatory compliance, such as Canada's Anti-Spam Legislation (CASL), often dictates consent expiration periods, meaning that after a certain period of inactivity or lack of direct engagement, your implied consent to email a user may expire. This adds a legal dimension to the risks of emailing very old, unengaged contacts.

Provider	Inactivity Period for Deletion
Google (Gmail)	2 years
Microsoft (Outlook.com, Hotmail)	2 years
Yahoo Mail	12 months (subject to change by ISP)
Other providers (e.g., ISPs)	Varies (often 3-12 months), check specific provider policies.

Strategies for re-engagement

While it's generally advised against emailing lists with such prolonged inactivity, if the business need is compelling, a highly cautious and strategic approach is paramount. You must prioritize protecting your email domain reputation above all else.

Start by identifying the true level of engagement. If no engagement (opens, clicks, website visits) has been recorded in four years, the risk is extremely high. Consider using an email validation servicelike Kickbox.io to identify known spam traps, invalid addresses, or risky contacts before sending anything. Even with validation, extreme caution is necessary.

If you absolutely must attempt re-engagement, segment these users into a small, isolated group. Send a very limited number of emails (e.g., 50-100 at a time) with a clear re-opt-in message. Have an extremely aggressive sunset policy: if there's no positive interaction after 2-3 sends, immediately remove them from your active mailing list. Remember, maintaining a clean, engaged list is more valuable than holding onto potentially harmful addresses.

Risks of broad sending

High bounce rates: Many addresses will be invalid or non-existent, leading to hard bounces that hurt reputation.
Increased spam complaints: Recipients won't remember you and will mark your emails as junk.
Spam trap hits: A significant danger that can lead to being blocklisted (or blacklisted).
Damaged sender reputation: ISPs will view you as a risky sender, impacting deliverability for all future campaigns.

Safe re-engagement approaches

Strict segmentation: Isolate these inactive users into a separate, small segment.
Email validation: Use a reputable service to clean the list before sending.
Low volume sends: Start with a very small batch to test engagement and monitor metrics.
Clear re-opt-in message: Clearly state the purpose of the email and offer an easy way to re-confirm interest.
Aggressive sunset policy: Remove contacts immediately if they don't engage after 2-3 re-engagement attempts.

Views from the trenches

Best practices

Actively manage your inactive users: sunset them after 6 months if they show no engagement to prevent future issues.

Segment and test: if re-engaging old lists, send small volumes with aggressive criteria for removal.

Prioritize consent: verify where old email addresses came from and if consent is still valid under regulations like CASL.

Define inactivity clearly: consider opens, clicks, or app usage as metrics, not just image loads, to assess true inactivity.

Common pitfalls

Assuming old users abandon mailboxes: they may still use the email but your emails are in spam.

Treating an old list like a new one: this greatly increases risk of spam complaints and hitting spam traps.

Ignoring brand relevance: if your brand or product has changed, old subscribers may no longer be a good fit.

Overlooking data security risks: a large database of inactive users can be a target for breaches.

Expert tips

Recency of engagement is far more important than the age of the account itself.

Consider reconfirming consent for users inactive for a very long time, especially for organizational domains.

A long tail of inactive customers might eventually click and purchase, but it could seriously damage your deliverability in the interim.

A user-centric approach is key; don't assume inactive users will magically convert if you just send the perfect email.

Marketer view

Marketer from Email Geeks says a normal practice is to sunset users after 6 months of inactivity and be very cautious with old lists. Emailing users inactive for 4 years risks spam complaints and hitting recycled or pristine spam traps. It's best to tread with caution and start with very low send volumes, perhaps 50, to gauge engagement.

2023-05-08 - Email Geeks

Marketer view

Marketer from Email Geeks says after four years, emailing a list is effectively like mailing a bought list, which carries significant risks.

2023-05-08 - Email Geeks

Prioritizing a healthy sender reputation

In conclusion, while the temptation to re-engage a large list of users inactive for four or more years can be strong, the risks far outweigh the potential rewards. The damage to your sender reputation, the increased likelihood of hitting spam traps, and the potential for regulatory non-compliance make such a venture highly ill-advised.

Focusing on a clean, engaged list is the cornerstone of good email deliverability. Instead of chasing ghosts, prioritize maintaining a healthy sender reputation by consistently cleaning your list, sunsetting truly inactive users, and concentrating your efforts on subscribers who genuinely want to hear from you.

This proactive approach ensures your emails consistently reach the inbox, fostering better relationships with your audience and driving real business results, rather than struggling with blocklists (or blacklists) and poor inbox placement.