Cold Email · Workflow

Deliverability Stack for Instantly

6 steps to clean domain infrastructure, warmed inboxes, a verified list, and active monitoring before your first send.

Written for operators No vendor influence Practical, not theoretical

Before You Start

Prerequisites: Instantly Growth, 2-5 domains, 4 tools

Setup time: 2-4 hours. DNS propagation: up to 48 hours. Account warmup: 2-4 weeks minimum before first live campaign.

📋
What you need

Instantly Growth plan or above. Domain registrar access to buy sending domains. Email verification tool (Bouncer, Clearout, or Emailable). GlockApps for seed testing. Unverified prospect list ready for upload.

Workflow Overview

6-step deliverability stack at a glance

StepActionToolOutput
1Register sending domainsDomain registrar2-5 new domains, separate from main domain
2Configure SPF, DKIM, and DMARCDNS provider / registrar panelAll three DNS records validated and resolving
3Connect accounts and enable warmupInstantlyAll inboxes connected, warmup running
4Verify prospect listBouncer / Clearout / EmailableInvalid and risky addresses removed
5Set per-account daily send limitsInstantlyVolume cap and ramp schedule defined
6Run seed tests and configure monitoringGlockApps / MailreachInbox placement confirmed before first send

Step by Step

All 6 steps: Instantly deliverability stack

  1. Register sending domains separate from your main company domain

    Buy 2-5 brand-variant domains (e.g., getyourbrand.com), point MX to Google Workspace or M365, never your primary domain. Plan 1 domain per 30-50 sends/day, max 2-3 inboxes per domain.

  2. Configure SPF, DKIM, and DMARC on every sending domain

    Add SPF (include:_spf.google.com for GWS), enable DKIM in your admin panel and copy the TXT record to DNS, then add a DMARC TXT at _dmarc.[yourdomain] with p=none and a rua address. Validate all three with MXToolbox before connecting any account to Instantly.

  3. Connect sending accounts to Instantly and activate warmup on every inbox

    Connect each inbox via Google OAuth or IMAP/SMTP, then enable Instantly's built-in warmup on each account. Run warmup at least 14 days before any live campaign and keep it active throughout sending.

  4. Verify your prospect list before uploading to Instantly

    Run your full list through Bouncer, Clearout, or Emailable and remove all Invalid, Risky, and Unknown contacts. Target a deliverable rate above 95% before upload.

  5. Set per-account daily send limits and define your volume ramp schedule

    Cap each account at 20-30 emails/day in week one, adding 10/week as reputation builds toward a 50/day ceiling. Use Instantly's timezone scheduling to spread sends across business hours, not a single burst.

  6. Run seed tests and set up recurring inbox placement monitoring

    Send a GlockApps seed test before launch and target above 85% inbox placement before any real sends. Schedule recurring seed tests weekly to catch reputation drops before they hit reply rates.

⚠️
Warmup: 2-4 weeks minimum

Sending from a fresh inbox without adequate warmup causes reputation damage that takes weeks to recover. Keep warmup active throughout all campaigns, not just during setup.

Common Failures

4 failure points in this Instantly stack and how to fix each

If
DKIM or SPF records are not validating in MXToolbox
DNS propagation takes up to 48 hours. If still failing after a full day, confirm you created a TXT record and that the SPF include matches your sending provider exactly.
Back to Step 2 →
If
Instantly rejects an account during connection
Enable IMAP in Gmail settings before connecting via SMTP. OAuth requires correct permissions and 2FA active; SMTP requires an app password, not your Google account password.
Back to Step 3 →
If
Seed tests show high spam placement after setup
Check DMARC policy and confirm SPF stays under 10 DNS lookups. Pause live sends, audit copy for spam triggers, reduce warmup volume, and re-test after 48 hours.
Back to Step 6 →
If
Bounce rate spikes above 3% in first live campaign
Unverified contacts or catch-all addresses slipped through. Pause immediately, re-verify the unsent segment, remove all role-based and catch-all addresses, and restart at reduced volume.
Back to Step 4 →

Stack Tools

3 tools outside Instantly: verification, DNS check, inbox monitoring

Bouncer
Email verification for Step 4. Scrubs invalid, risky, and catch-all addresses before upload to Instantly.
See Review
GlockApps
Seed testing and inbox placement monitoring for Step 6. Confirms DNS health and sender reputation before your first live campaign.
See Review
Mailreach
Runs alongside Instantly's native warmup for additional reputation scoring and inbox placement signals.
See Review

Stack built. Now evaluate your sending platform options.

Compare deliverability-first cold email platforms to see where Instantly fits against other high-volume senders.