Email Deliverability

Email deliverability is the likelihood that your emails reach the inbox instead of bouncing or landing in spam. It is the product of your infrastructure, sender reputation, list quality, and content, and it decides whether anything else about your email program matters.

Deliverability vs delivery rate

Delivery rate measures whether the receiving server accepted the message, see acceptance rate. Deliverability measures where the message landed after acceptance: inbox, promotions tab, or spam folder, see inbox placement. A 99 percent delivery rate with half of messages in spam is a deliverability problem, not a delivery problem.

What affects email deliverability

• Authentication: SPF, DKIM, and DMARC prove mail from your domain is really yours

• Sender reputation: complaint rates, bounce rates, and spam-trap hits tracked per domain and IP

• List quality: consent, hygiene, and removing addresses that hard bounce

• Engagement: mailbox providers watch opens, replies, and deletes-without-reading

• Content and volume: misleading subjects, link-heavy bodies, and sudden volume spikes all raise flags, see IP warming

How to improve email deliverability

Authenticate your domain, send only to people who opted in, remove bounces and long-inactive contacts, keep volume steady, and make unsubscribing effortless with one-click unsubscribe. Separate marketing and transactional streams so a risky campaign cannot drag down password resets. Our deliverability guide and why emails go to spam cover the full checklist.

How to measure deliverability

Watch bounce rate, spam complaint rate, and inbox placement. Google Postmaster Tools and seed-list testing show how major providers treat your domain. For a comparison of testing and monitoring options, see our roundup of email deliverability tools.

How Loops fits

Loops manages sending infrastructure, DNS setup, suppression, and volume shaping for SaaS teams, so transactional and marketing email each get the reputation treatment they need.

FAQ

What is a good email deliverability rate?
Aim for a bounce rate under 2 percent and a complaint rate under 0.1 percent, with the large majority of accepted mail landing in the inbox. Exact inbox rates vary by provider and audience.

Why do my emails go to spam?
The usual causes are missing authentication, a cold or damaged sender reputation, purchased or stale lists, and content that mismatches what recipients signed up for.

Does deliverability differ between Gmail and Outlook?
Yes. Each mailbox provider scores senders independently, so the same campaign can inbox at Gmail and land in junk at Outlook. Measure placement per provider.

Related: Inbox placement, Sender reputation, Email authentication, Email blacklist.