What could cause email deliverability or domain reputation to suddenly drop?

Marketer from Email Geeks shares that he's seen something similar for a few domains, where their deliverability dropped from Green to Yellow starting around 1/9. They are reputable senders who follow best practices and haven't changed any practices, introduced new lists, etc.

Marketer from Email Geeks explains that they've seen a dip in domain reputation (to low) since late December, with not much change in their mailing behavior.

Email marketer from StackOverflow answers that suddenly sending a large volume of emails after a period of low activity can flag your account with ISPs, because this is a common tactic by spammers. Phased rollouts should be adopted for new campaigns.

Email marketer from EmailOnAcid answers that if you start sending irrelevant content to parts of your list and they disengage you will have deliverability problems. List segmentation to send the right message to the right person is essential.

Email marketer from HubSpot explains that one of the top reasons deliverability suffers is when people are not given easy ways to unsubscribe. If they cant unsubscribe, they simply report it as spam.

Email marketer from ActiveCampaign explains that poor email design (high image to text ratios, use of non-standard fonts) can trigger spam filters. Designing for accessibility and using appropriate image optimization will help keep deliverability rates healthy.

Email marketer from GlockApps explains that certain words, phrases, or links in your email content can trigger spam filters, causing your emails to be directed to the spam folder. Reviewing content for spam triggers is a key task.

Email marketer from Mailjet explains that if your domain's email authentication records (SPF, DKIM, DMARC) are misconfigured or missing, mailbox providers may have difficulty verifying your legitimacy, leading to deliverability problems.

Marketer from Email Geeks shares that they found out on January 15th they were having increased user spam reports and were blacklisted on UCE, which blanket blacklisted anyone who uses AWS apparently.

Email marketer from Reddit explains that if your sending IP address has a poor reputation due to previous spam activity (even if not by you), mailbox providers may block or filter your emails. Sharing IPs with spammers can impact your own deliverability.

Email marketer from Litmus explains that domain reputation depends on your reputation with ISPs, the quality of your content, and the quality of your email list, and that consistently low engagement rates and high spam complaints will affect your domain reputation.

Email marketer from SendPulse shares that sending emails to a list with a high percentage of invalid, inactive, or spam trap email addresses will damage your sender reputation and result in deliverability issues.

Expert from Word to the Wise (Laura Atkins) explains that sending reputation is not a static thing but is constantly evolving. She notes that monitoring and actively managing your sender reputation is vital for ensuring deliverability.

Expert from Email Geeks explains that Google isn’t going to pay attention to UCEProtect but the increased spam reports are an issue.

Expert from Word to the Wise Staff explains that correctly configured SPF, DKIM, and DMARC records are crucial for email deliverability. Incorrect or missing authentication can make it appear as if emails are being spoofed or sent from unauthorized sources, thus damaging deliverability.

Expert from Spam Resource (John Levine) explains that hitting spam traps will cause immediate deliverability problems. Spam traps are email addresses used to identify spammers. Sending to a spam trap is a clear indicator of poor list hygiene or malicious activity.

Expert from Email Geeks shares that she is not seeing any changes as she checks client domains.

Documentation from Microsoft shares that sudden changes to your sending patterns, such as a large increase in email volume, can trigger filters and negatively affect your deliverability and domain reputation. Consistent sending habits help establish trust with mailbox providers.

Documentation from Google Postmaster Tools Help explains that a sudden increase in spam complaints will negatively impact your sender reputation and deliverability. Users marking emails as spam directly signals to mailbox providers that the emails are unwanted.

Documentation from RFC explains that being listed on a blocklist (also known as a blacklist) is a major cause of deliverability issues. Blocklists are used by mailbox providers to filter out suspected spam and malicious emails.

Documentation from SparkPost says that ignoring feedback loops (FBLs) can hurt your deliverability, especially if you are flagged as spam. These are direct channels from the ISP which advise you of complaints.