Overview
Email deliverability is your ability to land emails in the recipient's inbox instead of spam. It depends on your domain authentication, sender reputation, email content, and sending behavior. This guide is a high-level checklist that links to detailed setup articles. Complete the pre-flight items once before your first campaign, then follow the ongoing practices to maintain a strong sender reputation over time.
Pre-Flight Checklist
Complete these one-time tasks before sending your first campaign:
Avoid using a subdomain. Using a subdomain is not ideal at all, and your email availability would really be bad if you use it.
Always use a burner domain so that your main domain and mail business domain address is not harmed.
Authenticate your domain Add SPF, DKIM, and DMARC TXT records to your DNS so email providers can verify your identity and bypass spam filters.
Run a Domain Setup Check Go to Outreach → Email Senders → Actions → Domain Report. Review the report for SPF, DMARC, DKIM, and custom tracking domain status. Fix any failed checks.
Warm up your senders Enable WarmUp for 15–30 days before sending cold emails. This automatically sends emails, opens them, clicks links, and moves them from spam to inbox. We have 100,000+ Active email addresses in our warmup pool network. Not available for SMTP-only accounts.
Set up a custom tracking domain Replace default tracking URLs with your branded domain to improve trust and avoid spam flags. Use a subdomain if you have a live website on your root domain.
Verify your lead lists Clean lists before sending to protect your sender reputation and reduce bounces.
Skip Email Security Gateways Configure which ESGs (Barracuda, Mimecast, Proofpoint, Cisco) to skip in Account → Settings, then enable Skip leads using Email Security Gateways in your sequence to avoid hard bounces from gateway-protected inboxes.
Create a professional signature Keep it simple, assign it to your sender, and use
{{email_signature_of_sender}}in templates.
Ongoing Best Practices
Follow these habits to maintain and improve deliverability over time:
Send plain text emails — Avoid heavy HTML and images in initial emails. Select Plain Text format in templates for better inbox placement.
Use AI Spintax — Enable spintax in sequences to create multiple copy variations and avoid sending identical emails repeatedly. Add variations to subject lines, greetings, and CTAs:
{{ Hey {first_name} | Hi {first_name} }}, {{ I came across {company_name} | I was checking out {company_name} }}... {{ Mind if I send over a quick loom? | Worth a 3-minute video? }}Disable open and click tracking — In Sequence Settings, turn off open tracking and avoid default click tracking to reduce spam signals. If links are needed, use a custom tracking domain.
Enable Random Delays and Sending Hours Add 2–7 minute random delays (at least 5 minutes for Outlook senders) and restrict sending to business hours to mimic human behavior. Even when disabled, SalesBlink leaves a short random gap of a few seconds between emails from the same sender (at least 5 minutes for Outlook senders).
Follow daily sending limits — Start at 10–20 emails/day for new senders, ramp to 20–30 after the first 1–2 weeks, and stay at 30–50 emails/day per sender once established. This applies regardless of your email provider (Google Workspace, Outlook, etc.). Set limits in Email Senders → Sender Settings → Daily Sending Limit.
Avoid images and links in the first email — If follow-up emails need links, use a custom tracking domain instead of default tracking URLs.
Refresh templates regularly — Update copy weekly or bi-weekly to prevent repetition-based spam detection and keep content relevant.
Run multiple sequences — Diversify sending patterns instead of relying on a single sequence to maintain natural behavior.
Monitor sender health — In Outreach → Email Senders, click the Health icon to review the sender's score. Scores in the 90s mean the sender is ready or nearly ready for outreach; 85–90 usually means the sender is healthy but readiness is held only by a provider-level spam caution that clears on its own within days; lower scores mean warmup is still progressing or the sender has a deliverability or connection issue. Open the sender's WarmUp Report and Domain Report to see exactly what is holding it back.
Use multiple senders and folders — Connect unlimited senders and organize them into folders to rotate sending and increase daily capacity. Start with at least 4 Google Workspace Gmail and 4 Outlook mailboxes so provider matching can route each lead through the same provider ecosystem. Order Done-For-You Gmail or Done-For-You Outlook mailboxes from SalesBlink if you want a fully managed setup.
Tip: Use one sender, or one sender folder, per sequence to avoid confusion over daily limits and scheduling.
Filter WarmUp emails — All WarmUp emails contain your Warmup Filter Tag in the subject. Create a filter in your email client to hide them from your inbox.
Troubleshooting
| Cause | Solution |
|---|---|
| Sending too fast from a new account | Slow down volume; warm up gradually |
| No email warm-up history | Enable Email WarmUp |
| Spam-like content | Remove spam keywords; use natural language |
| Low engagement | Improve targeting and subject lines |
| High bounce rates or complaints | Clean your lead lists; verify emails |
| Missing SPF, DKIM, or DMARC | Complete domain technical setup |
| Using default tracking domains | Set up a custom tracking domain |
| High sender health but emails still land in spam | See why this happens — cross-provider filtering |
| Heavy HTML or images in emails | Switch to plain text format |
Note: New email accounts typically need 2–4 weeks of warm-up before high-volume sending.
Results
Following these practices helps:
- Improve inbox placement
- Reduce spam flags
- Increase engagement and conversions
- Build long-term sender reputation
- Maximize the ROI of your cold email campaigns
For detailed setup guides, refer to the linked articles throughout this checklist.