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How to Improve Email Deliverability with Apollo

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Overview

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Effective email outreach starts with your sending setup and continues with relevant messages and regular monitoring. Use Apollo to review your domain authentication, prepare your mailboxes, and identify sending issues that need attention.

Check out the following sections to improve your email deliverability with Apollo.

 
Deliverability Delivered

Explore Chapter 7 of Apollo's Outbound Sales guide for more guidance on email deliverability and spam filtering.

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Improve your email deliverability

Follow this five-part checklist before you launch outreach and return to it as you review performance. Start with your domains and mailboxes, then review your audience and message. Once you're sending, use performance data and diagnostic results to decide what needs attention.

Deliverability checklist
Check your domain authentication
Prepare your mailboxes
Review your recipients and content
Monitor your sending health
Address sending issues

Check your domain authentication

Start with the domains used by your sending mailboxes. SPF, DKIM, and DMARC records help receiving email providers verify your messages. Review authentication for each sending domain, especially when you connect a mailbox that uses a different domain.



A tracking subdomain serves a different purpose from your sending domain. Setting one up doesn't replace sending-domain authentication. If you need help changing DNS records, contact the person who manages your domain.

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Prepare your mailboxes

Once you've checked your sending domains, prepare each mailbox you plan to use for outreach. Review its connection, sender signature, and sending limits. Treat Email Warmup as a separate preparation decision with its own requirements.




Warmup is optional and uses a third-party service. Review the linked guide before enrolling a mailbox, including access requirements and applicable costs.

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Review your recipients and content

With your sending setup ready, focus on who you're contacting and why your message matters to them. A verified email address and a relevant prospect are separate checks: review both before adding someone to outreach.




For example, when contacting a sales operations manager, explain how your offering addresses a relevant reporting or process challenge. Keep the message focused on that need instead of listing every feature. Use clear formatting and review the message before sending.

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Monitor your sending health

After outreach begins, review performance regularly. Check your mailbox and domain setup alongside sequence results so you can identify where to investigate. Use diagnostic tests when you need more information about a deliverability concern.



Choose your next action based on the result. Bounced emails call for reviewing the reported bounce reason. A blocklist result calls for checking the identified provider. Low replies also warrant reviewing your targeting and message.

Inbox placement tests show where messages land in test mailboxes. Use the results as a diagnostic signal, not the exact percentage of emails reaching your prospects' inboxes.

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Address sending issues

Use the reported error or diagnostic result to select the appropriate troubleshooting guidance. Investigate the specific issue before changing your sending setup.




Before contacting support, note the affected mailbox or sequence, the exact error message, and the steps you've already tried. Include the relevant diagnostic result so you can clearly explain what happened.

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Next Steps

Use these guides for detailed setup and monitoring instructions.

Diagnose and Fix Domain Authentication on Apollo Review and correct your sending domain's DNS records.
Configure Email Sending Limits Control the volume and timing of emails sent from your mailbox.
Manage Mailboxes and Domains on Apollo Review mailbox health and run diagnostic tests.
Report on Sequences Review sequence performance and identify areas that need attention.

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