Deliverability 101: landing in the inbox

"Deliverability" is whether your email actually reaches the inbox. Great content doesn't matter if it lands in spam. Here's how to keep your sending healthy.

Start with the basics

• Verify your reply-to address so replies reach an inbox you actually read. See Set up and verify your reply-to address.
• Only email people who opted in. Permission is the whole foundation.
• Keep your business name and mailing address set so every send is compliant. See Add your business name and mailing address.

Warm up gradually

Sending to a list for the first time? Don't blast everyone at once. Start with your most engaged contacts and raise the volume over several sends. A brand-new sender with a sudden spike in volume looks exactly like a spammer to a mailbox provider.

Keep your list clean

• Let Thunk Mail suppress bounces, unsubscribes, and complaints on its own. Don't re-add them. See How bounces, unsubscribes, and complaints work.
• Drop contacts who haven't opened anything in a long time. A small engaged list beats a big cold one.

Write emails people want

• Keep the subject line clear and honest. No ALL CAPS, no "FREE!!!" hooks.
• Balance images against text. An email that's one giant image is a classic spam signal.
• Always include a working unsubscribe link. Thunk Mail adds it for you.

Watch your metrics

After each send, check your open, click, bounce, and complaint rates. Rising bounces or complaints are the early warning. A complaint rate sustained above roughly 0.1% needs action: pull back your volume and rebuild around the people who actually engage.

Good deliverability is a habit rather than a setting. Send relevant email to people who asked for it and the inbox mostly takes care of itself.

Already in trouble? Why are my emails going to spam? is the troubleshooting version of this page.