Why Are My Emails Going to Spam? Diagnosis & Fix Guide

Gmail, Outlook, and Yahoo all treat SPF hard fails and DMARC alignment failures as high-spam-probability signals. If your authentication is misconfigured, ~70% of filters flag you immediately.

Gmail and Outlook assign reputation scores to your sending domain and IP. Low reputation (from previous spam complaints, bounce rate spikes, or engagement drops) triggers spam filtering. This is invisible until you monitor it.

If you're on a shared IP pool with other senders, one bad actor can damage reputation for everyone on that pool. You inherit the behavior of thousands of other senders.

Bounce rates above 3% signal list quality problems to ISPs. Hard bounces indicate invalid addresses; soft bounces indicate mailbox full or server issues. Both harm reputation.

Gmail enforces a hard limit: spam complaint rates above 0.3% trigger bulk sender protections, which can move entire campaigns to spam. Even rates at 0.2% start degrading placement.

ISPs use engagement as a reputation signal. If 50%+ of your recipients ignore your emails, filters assume the emails are unwanted. Low engagement compounds other problems.

Certain keywords and patterns (urgency language, CAPS LOCK, too many links, embedded executables, etc.) trigger spam score increases. Content filtering is less common now than reputation filtering but still matters.

1. Run DMARC, SPF, and DKIM record checkers to identify misconfigurations
2. For SPF: ensure your ESP is listed in your SPF record (check your ESP documentation for the exact SPF string)
3. For DKIM: verify DKIM record is published in DNS and matches your ESP's signing domain
4. For DMARC: set policy to "monitor" (p=none) first, collect data for 1 week, then move to "quarantine" (p=quarantine) once aligned
5. Test authentication with a seed list or InboxEagle: send a test campaign and verify all three pass before scaling

1. Set up Google Postmaster Tools and check domain reputation weekly
2. If reputation is low, reduce sending volume by 50% for 3-5 days
3. Check for bounce spikes: investigate hard bounces and remove them immediately
4. Review complaint rates: if above 0.2%, implement re-engagement campaign to remove disengaged subscribers
5. Check if your ESP moved you to a new shared IP recently: if so, reputation rebuild takes 1-2 weeks

1. Remove all hard bounces from previous sends (invalid email addresses)
2. Remove unengaged subscribers: anyone who hasn't opened in 90+ days
3. Remove complainers from the past 6 months
4. Consider a re-engagement campaign: send to unengaged subscribers offering to update preferences; remove anyone who doesn't click
5. After cleaning, your bounce rate should drop below 2% and complaint rate below 0.2%

1. If reputation is low, temporarily reduce sending to your most engaged subscribers only
2. Send to "gold" segment (high open/click rates) for 5-7 days before sending to full list
3. Monitor Google Postmaster Tools and reputation metrics daily
4. Once reputation improves, gradually expand to broader segments
5. Full recovery typically takes 1-4 weeks depending on severity

1. If your sending volume justifies it (100K+/month), request a dedicated IP from your ESP
2. Dedicated IPs start with zero reputation: warm up gradually (10K on day 1, 20K on day 2, etc.) over 7-10 days
3. Monitor reputation daily during warm-up
4. Once warm-up is complete, you control the IP's reputation entirely