Discovering your emails are marked as spam can be frustrating. This typically happens due to sender reputation issues, content triggers, or technical misconfigurations. Understanding these factors is the first step toward ensuring your messages reach the inbox.

Your sender reputation is a score assigned by email providers (like Gmail or Outlook) based on your sending history. A poor reputation, often caused by high bounce rates or recipient spam complaints, will almost guarantee your emails are filtered. To maintain a good reputation:

• Use a dedicated IP address for bulk sending if possible.
• Regularly clean your email list to remove invalid addresses.
• Always include a clear, one-click unsubscribe link.

Email content is heavily scanned by filters. Avoid these common red flags:

• Excessive use of ALL CAPS, exclamation points!!!, or spam-trigger words like "FREE" or "Guaranteed".
• Poor HTML code with broken tags or very large image-to-text ratios.
• Missing a physical mailing address in the footer, which is legally required in many regions.

Technical setup is crucial. If your domain's authentication records are not correctly configured, providers cannot verify you are a legitimate sender. Ensure these three key DNS records are properly set up for your domain:

1. SPF (Sender Policy Framework): Specifies which servers can send email for your domain.
2. DKIM (DomainKeys Identified Mail): Adds a digital signature to prove the email wasn't altered.
3. DMARC (Domain-based Message Authentication, Reporting & Conformance): Tells providers what to do if SPF or DKIM checks fail and provides reporting.

Missing these is like sending mail without a return address.

Finally, engage with your audience. High open and reply rates signal to providers that recipients want your emails. Start by sending relevant, valuable content to subscribers who explicitly opted in. By focusing on reputation, content, and technology, you can dramatically improve your email deliverability and keep your communications out of the spam folder.