Cold Emails That Actually Land in the Inbox
Deliverability is the foundation of every cold email program. Without it, the best copy and targeting in the world won't get you replies. We handle domain setup, DNS authentication, inbox warmup, and ongoing monitoring - so your outreach has a real shot at being seen.
Your Emails Can't Convert If They're Going to Spam
Most companies underestimate how much deliverability affects results. If your emails are landing in spam or promotions folders, your open rates, reply rates, and ultimately your pipeline suffer - regardless of how good your copy is.
Deliverability is part technique (domain setup, DNS records, sending infrastructure) and part behavior (warmup cadence, sending limits, list hygiene). We handle both sides so your campaigns launch on a clean foundation.
Common Deliverability Failures
- Sending from your primary domain (puts your brand at risk)
- Missing or misconfigured SPF, DKIM, or DMARC records
- Jumping to full sending volume without warmup
- Too many emails per day per mailbox
- No custom tracking domain (hurts reputation)
- Sending to unverified or stale lists
Full Email Deliverability Setup
Sending Domain Configuration
We register and configure separate sending domains for cold email - distinct from your primary business domain. This protects your brand domain's reputation while still representing your company credibly.
DNS Authentication Records
SPF, DKIM, and DMARC records configured correctly for each sending domain. We verify each record after setup and test deliverability using tools like Mail-Tester and Google's Postmaster before any campaigns launch.
Mailbox Setup and Connection
Google Workspace or Microsoft 365 mailboxes created, configured, and connected to Apollo.io. We handle the OAuth connection, forwarding setup, and initial account configuration for each sending mailbox.
Inbox Warmup Strategy
New mailboxes need to build sending reputation before running cold campaigns. We configure Apollo.io's inbox warmup feature and establish a warmup timeline - typically 2-4 weeks before ramping to full volume.
Sending Limit Ramp-Up Schedule
We set and track daily sending limits per mailbox, incrementing safely over time. Starting at 10 emails/day and scaling to 35/day over 5-6 weeks based on deliverability scores. Includes per-hour throttling to stay within safe ranges.
Ongoing Deliverability Monitoring
Weekly review of Apollo.io's Deliverability Suite - checking scores, flagging at-risk mailboxes, and adjusting sending limits. We monitor for spam complaints, bounce rates, and inbox placement issues and act before they become problems.
How We Ramp Up Sending Volume Safely
| Timeframe | Daily Emails per Mailbox | Emails per Hour | Notes |
|---|---|---|---|
| Week 1-2 (Warmup Only) | Warmup traffic only | N/A | No cold outreach yet |
| Week 3 | 10/day | 3/hour | Campaigns launch |
| Week 4 | 15/day | 3/hour | First increment |
| Week 5 | 20/day | 6/hour | Bump to 6/hour at 16+ |
| Week 6 | 25/day | 6/hour | If score stays above 85% |
| Week 7 | 30/day | 6/hour | Continued good score |
| Week 8+ | 35/day | 6/hour | Maximum recommended limit |
Deliverability Score Requirements
We only increment sending limits for mailboxes with a deliverability score of 85% or above in Apollo.io's Deliverability Suite. Mailboxes below that threshold get held at their current limit until the score recovers. Mailboxes with "No data" are not eligible for ramp-up until a score is established.
What Healthy Deliverability Looks Like
85%+
Deliverability Score
Apollo.io's minimum score to qualify for sending limit increases
<3%
Bounce Rate
Target bounce rate for cold campaigns. Above this signals list quality issues.
<0.1%
Spam Complaint Rate
Google and Microsoft thresholds for safe sending. Stay well below this.
Frequently Asked Questions
If your cold email domain gets flagged or blacklisted, it only affects that domain - not your primary company domain. This is standard practice. We use domains that are clearly related to your company (e.g., yourcompany-mail.com) so recipients can verify your identity without risk to your brand.
At 35 emails per mailbox per day, you need roughly one mailbox per 700 contacts per month (assuming a 3-step sequence with some overlap). Most clients start with 2-4 mailboxes and scale from there. We help you right-size based on your target volume.
2-4 weeks for new mailboxes before we launch campaigns. We run warmup in parallel with Apollo.io setup and copy review, so it doesn't add time to the overall timeline - campaigns are ready to launch when warmup is complete.
Inbox warmup (Apollo.io's built-in feature) sends small volumes of automated warmup emails between mailboxes to build a positive sending reputation before you launch campaigns. Sending ramp-up is the process of gradually increasing your campaign daily sending limit over time, based on your deliverability score. Both matter. We do both.
Yes - deliverability monitoring is included in all our ongoing management plans. We review Apollo.io's Deliverability Suite weekly, flag any mailboxes dropping below 85%, and adjust limits or pause sending if a problem develops. We also monitor Google Postmaster for domain reputation signals.
Related Reading
- Email infrastructure for cold outreach (March 2026) - domains, mailboxes, warmup, and infra setup
- Cold email best practices for SaaS companies
- Top 12 cold email mistakes to avoid
- Apollo.io Strategy and Setup - deliverability as part of a full Apollo.io build
- Done-for-You Outbound System - deliverability runs inside the full outbound engagement
Start With a Solid Deliverability Foundation
Whether you're setting up cold email for the first time or trying to fix deliverability issues with an existing setup, let's talk about what's needed.
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