Key takeaways
- Deliverability means inbox placement, not just 'delivered' - a campaign can show 99% delivered and still earn nothing.
- Authenticate with SPF, DKIM and DMARC; since 2024 Gmail and Yahoo require all three from bulk senders.
- A smaller, engaged list almost always beats a large, stale one.
- Warm up new domains gradually and monitor placement with tools, not guesswork.
Deliverability is not the same as delivery
Delivery means a mailbox provider accepted your message. Deliverability means it actually reached the inbox a person checks. A campaign can show 99% delivered and still earn almost nothing because most of it landed in Spam or the Promotions tab. Inbox placement is the number that matters.
Authenticate your sending
Authentication proves you are a legitimate sender. Three records do the work:
- SPF lists the servers allowed to send for your domain.
- DKIM adds a cryptographic signature mailbox providers can verify.
- DMARC ties the two together and tells providers what to do with messages that fail.
Since 2024, Gmail and Yahoo require bulk senders to authenticate with all three, offer one-click unsubscribe, and keep spam complaints low. Getting this right is the single biggest lever for most senders.
Keep your list clean
Sending to people who never open trains mailbox providers to treat you as spam. Remove hard bounces, suppress chronically unengaged subscribers with a sunset flow, and never buy or scrape lists. A smaller, engaged list almost always outperforms a large, stale one.
Earn engagement
Opens, clicks, and replies are positive signals; spam complaints and deletes are negative ones. Send relevant, well-segmented content, make unsubscribing easy, and keep your complaint rate well under Gmail's 0.30% threshold.
Warm up and monitor
If you are on a new domain or rebuilding reputation, ramp volume gradually rather than blasting your whole list at once. Then monitor placement with tools like GlockApps and Google Postmaster Tools so problems show up in a dashboard, not in your revenue.
Want to know where your email is landing?
We will run an inbox-placement audit across the major providers and send you the findings - no retainer required.