Why Your Klaviyo Campaigns Are Landing in Spam (and How to Fix It)
· 7 min read
The most common deliverability killers for e-commerce senders, ordered by how often we see them — and how to work out which one you have.
1. Authentication gaps
The single most common cause we see: SPF or DKIM missing on one or more platforms. Your Shopify notifications might be authenticated while your Klaviyo flows aren't — or Klaviyo is using its shared sending domain instead of a branded one tied to yours.
Inbox providers now expect every bulk sender to authenticate with their own domain. Since 2024, Gmail and Yahoo require it outright for anyone sending at volume.
2. List problems
Stale subscribers who haven't opened in a year drag your engagement down, and low engagement tells Gmail your email isn't wanted. Add old purchased or imported lists, and spam traps start appearing.
Suppression management — automatically removing bounces, complainers, and long-term unengaged contacts — is one of the cheapest deliverability wins available.
3. Sending pattern spikes
Sending 5,000 emails a week and then 80,000 on Black Friday looks exactly like a spammer's burst. Providers throttle or filter sudden spikes from domains without an established pattern.
Ramp volume up gradually in the weeks before a big campaign, and segment so your most engaged customers get the first sends.
4. Content triggers: the honest, short list
Content matters less than most people think — but a few things genuinely hurt: image-only emails with almost no text, link shorteners, mismatched link domains, and broken HTML from heavy templates.
“FREE” in a subject line on its own won't sink you. A bad reputation plus an all-image email will.
How to diagnose which one you have
Start with authentication — it's binary, and easy to verify. Then check Google Postmaster Tools for your domain reputation and spam rate. If both look clean, look at list engagement and sending patterns.
If that sounds like a lot, it's exactly what our free audit covers. You'll get a prioritized list of what's wrong and what to fix first.