How to Avoid the Spam Folder: A Comprehensive Checklist

Landing in spam is the death of a cold email campaign. This checklist covers every factor that influences spam placement.

Infrastructure checklist

SPF record configured correctly — verify with SPF Checker. DKIM enabled and passing — verify in email headers. DMARC record published — verify with DMARC Checker. Domain not on any blacklists — verify with blacklist checker. Domain age at least 14 days, ideally 30+ days. Email accounts warmed for at least 14 days. Warmup running alongside active campaigns. Custom tracking domain configured (if tracking is enabled).

Content checklist

No spam trigger words (free, guaranteed, act now, limited time, click here). No excessive capitalization or punctuation. No HTML formatting — plain text only. No images in the first email. No links in the first email (or minimal links in follow-ups). Short email length (under 100 words in body). Personalized content with variables and Spintax. Natural, conversational tone.

Sending behavior checklist

Daily volume per account under 50 total (warmup + campaigns). Gradual ramp-up for new accounts (no sudden volume spikes). Time gaps between sends (2 to 5 minutes minimum). Sending during business hours in recipient's time zone. Inbox rotation across multiple accounts.

List quality checklist

All addresses verified within the last 30 days. Bounce rate below 2%. No role-based addresses (info@, sales@). No previously bounced or complained addresses. Suppression list cross-referenced. This checklist is also available as a printable resource in the deliverability playbook at Warm Inboxes.

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