Why did my promotional emails suddenly start going to the spam folder after terminating my deliverability agency contract?

Email marketer from Stackoverflow explains that to ensure good delivery you need to use a dedicated IP address for each domain you send from.

Email marketer from Quora explains that before terminating a contract, clarify whether the agency was suppressing cold leads (and what those criteria were) and what the engagement levels of those users were. If this stops it can cause problems.

Email marketer from Sendinblue Support responds that sudden spam filtering can be caused by various factors including changes in email content (triggering spam filters), a decrease in engagement, or an increase in spam complaints. It recommends monitoring these metrics and adjusting strategies accordingly.

Marketer from Email Geeks explains that landing emails in the primary tab is a combination of factors and signals like reputation, engagement, and user behavior, and suggests checking reputation and engagement KPIs.

Marketer from Email Geeks suggests not panicking over one test email showing spam placement in Glockapps, as it uses seed IDs, and recommends testing with internal Gmail test accounts for a more accurate view.

Email marketer from Reddit responds that agencies often manage IP reputation through dedicated IPs and warming schedules. Ensure you have access to the same IPs or gradually transition to new IPs with proper warming to avoid sudden deliverability drops after ending the contract. User also recommends checking throttling settings are the same and if the sending volume has changed.

Email marketer from Mailjet Support explains that agencies often implement sender authentication and IP warming strategies. After termination, ensure these configurations remain active and are properly managed internally to avoid deliverability issues.

Email marketer from Neil Patel's Blog shares that a sudden drop in deliverability after ending a contract often points to a lack of consistent email marketing best practices. He suggests reviewing sender reputation, authentication (SPF, DKIM, DMARC), and engagement metrics.

Expert from Email Geeks explains that bad delivery for a single email could be related to something specific to that email and not necessarily indicative of ongoing deliverability problems.

Expert from Spamresource.com explains that a common cause of deliverability problems is an IP address ending up on a block list. This can happen if the email provider shares IPs. Using dedicated IP addresses can help.

Expert from Word to the Wise explains that agencies often manage sender reputation and that transitioning away from their infrastructure can negatively impact deliverability if not managed correctly. She recommends auditing authentication settings, IP reputation, and engagement metrics during and after the transition.

Expert from Email Geeks suggests waiting for bad delivery to occur over multiple sends/days before making changes, as it often resolves itself and a few days isn't enough for a significant reputation impact.

Documentation from DMARC.org details that a DMARC policy helps email receivers handle messages that fail authentication checks. A sudden shift in DMARC policy enforcement (e.g., from 'none' to 'quarantine' or 'reject') can cause deliverability problems if not properly configured and monitored after agency changes.

Documentation from Microsoft explains you should make sure your domain name is registered. Microsoft also advises that you should use an email service provider to send bulk emails to ensure a good reputation and that email authentication is also setup correctly

Documentation from RFC-Editor shares that Sender Policy Framework (SPF) records must be correctly configured to authorize sending mail servers. Incorrect or missing SPF records can lead to emails being marked as spam, especially after transitioning from a managed service.

Documentation from Google explains that Gmail's spam filtering algorithm considers numerous factors, including sender reputation, authentication records, user engagement, and content quality. Significant changes to any of these factors can impact inbox placement.