Sending an email does not guarantee it lands in the inbox. Email providers run automated checks on every message before delivery, and if something looks off, your email can end up in a guest's spam or junk folder even if it was sent successfully from the platform.

This article explains the most common reasons this happens and what you can do about it.

Topics

• How spam filters work
• Common reasons emails go to spam
• What you can do
• FAQ

How spam filters work

Every email provider (Gmail, Outlook, Yahoo, and others) runs its own spam filter. These filters score each incoming email based on a range of factors: who sent it, how the sender has behaved in the past, what the email contains, and how recipients have engaged with similar messages. If the score crosses a threshold, the email is moved to spam automatically, without notification.

No two filters work exactly the same way, which means an email that reaches one guest's inbox may land in another's spam folder.

Common reasons emails go to spam

Poor sender reputation Your sender reputation is a score that inbox providers assign to your sending domain based on your history. High bounce rates, spam complaints, and sending to inactive addresses all lower your score over time. A low score means more of your emails get filtered.

Spam-trigger content The content of your email matters. Subject lines or body copy that use phrases like "FREE!!!", excessive caps, or too many exclamation marks can trigger spam filters. Oversized images, broken links, or an imbalanced image-to-text ratio can also cause issues.

Low engagement from your list Inbox providers pay attention to how recipients interact with your emails. If guests consistently ignore, delete, or do not open your messages, providers interpret this as a signal that your emails are unwanted — and start routing them to spam.

Spam complaints When a guest marks your email as spam, it sends a direct signal to their inbox provider. Even a small number of complaints can affect your deliverability. The industry benchmark is to stay below 0.1% — that is one complaint for every 1,000 emails sent.

Sending to unengaged or invalid contacts Emailing contacts who have not engaged in a long time, or who have invalid email addresses, increases your bounce rate and lowers your sender reputation.

What you can do

• Keep your contact list clean. Remove contacts who have not engaged with your emails in the last three to six months. Sending to an engaged list always outperforms sending to a large, stale one.
• Review your content. Avoid spam-trigger words, overly promotional subject lines, and emails that are mostly images with very little text.
• Make unsubscribing easy. A guest who can easily unsubscribe will do so instead of marking your email as spam. A spam complaint is far more damaging than an unsubscribe.
• Send consistently. Sending regularly (weekly or fortnightly) keeps your domain warm and signals to providers that you are a legitimate sender. Sudden large spikes in volume can raise red flags.

Note: If your emails are consistently going to spam and the steps above have not resolved it, contact our support team at support@meandu.com. Deliverability issues can sometimes require investigation of your sending domain or authentication setup.

FAQ

A guest says your email went to their spam. Does that mean all your emails are going to spam? Not necessarily. Spam filtering is done per inbox provider and can vary per recipient. One guest's spam folder does not mean your whole campaign is affected but it is worth checking your overall open rates and complaint levels to see if there is a wider pattern.

Can a transactional email go to spam? Yes. Deliverability and consent are separate things. A voucher or reward email can still land in spam if your sender reputation is low or the guest's provider filters it. See our article on transactional and marketing emails for more detail.

Is there anything the platform does to help with deliverability? The platform sends your emails through trusted infrastructure, but your sending behaviour, list quality, content, and engagement — is what ultimately determines inbox placement.

Any questions? Reach out to us via email at support@meandu.com.