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Complaint
Also known as: Spam Complaint
When someone clicks the spam or junk button on your email instead of unsubscribing. That action tells inbox providers your email was unwanted and counts as a complaint against your sending reputation.
A complaint happens when a person tells their email provider that your message is spam. They do this by hitting the spam or junk button in their inbox. That click is recorded and passed back to your email platform. It is one of the strongest negative signals you can get as a sender.
Email providers watch your complaint rate closely. If too many people complain, your future emails start to land in spam instead of the inbox. Even a small number of complaints can hurt your domain and IP reputation. This is why serious senders track complaints on every campaign.
To keep complaints low, set clear expectations at signup and send what people asked for. Make it easy to unsubscribe in one click so people do not feel trapped. Regularly remove cold subscribers who have not opened in a long time. A smaller list of engaged people is safer and usually performs better.
Related Terms
Email Appending
Email appending is when you use a third party to add email addresses to your existing customer records based on other details like name or postal address. It is risky because these people did not ask to hear from you, which often leads to spam complaints and poor deliverability.
Learn more →Reputation(Sender Reputation)
Sender reputation is the trust score mailbox providers give your emails based on how you send and how people react. It helps decide if your messages land in the inbox or get pushed to spam.
Learn more →Triggered Email
A triggered email is a message your system sends automatically when someone does something specific, like signing up, leaving items in a cart, or reaching a milestone. It goes to one person based on their action instead of going to your whole list at a fixed time.
Learn more →Domain Reputation
How trusted your sending domain is by email providers like Gmail and Outlook. A strong domain reputation keeps your emails in the inbox instead of spam.
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