Authentication

0/5

SPF record published and passing for all sending IPs

Check with MXToolbox SPF Lookup - should show all your ESP servers as authorized

DKIM signing enabled and keys published in DNS

Send a test email and check headers for dkim=pass in Authentication-Results

DMARC record published (at minimum p=none)

Required by Google and Yahoo for bulk senders since February 2024

DMARC rua= reporting email receiving aggregate reports

Review weekly for unauthorized senders and authentication failures

Sending IP has valid reverse DNS (PTR record)

Your ESP handles this for shared IPs; verify if using a dedicated IP

Warmup & Reputation

0/5

Domain has completed a 21–30 day warmup program

Do not launch campaigns from a fresh domain without warmup

Inbox placement rate above 95% across Gmail and Outlook

Verify with MailPilot placement monitoring or seed list tests

Gmail Postmaster Domain Reputation shows "High"

Check at postmaster.google.com - only register your sending domain

Sending domain and IP are not on any major blacklist

Check Spamhaus, Barracuda, and SURBL via MXToolbox Blacklist Check

Gmail Postmaster spam rate is below 0.08%

Google enforces 0.10% - stay below 0.08% as a safety buffer

List Quality

0/5

List was NOT purchased or scraped

Purchased lists have high concentrations of spam traps and invalid addresses

Email addresses verified before sending

Use an email validation service to remove invalid and disposable addresses

Hard bounce rate from previous sends is below 2%

Above 3% is a warning; above 5% pause sending and clean the list

Contacts inactive for 90+ days have been suppressed or removed

Sending to disengaged contacts hurts your engagement rate and sender score

One-click unsubscribe is working and honored within 2 days

Required by Google and Yahoo bulk sender requirements since 2024

Email Content

0/5

Cold outreach uses plain-text format (no heavy HTML)

Complex HTML templates have higher similarity to mass marketing emails in spam models

No URL shorteners used in links

bit.ly and similar shorteners trigger spam filters - use the full destination URL

Email has a single, clear call-to-action

Multiple CTAs reduce reply rates; one clear ask outperforms a list of options

First line is personalized for each recipient

Specific first sentences push open rates 35–50% vs generic openers at 18–24%

From name matches expected sender (not brand name for cold email)

Person name (John Smith) outperforms company name (Acme Corp) for cold outreach

Sending Behavior

0/5

Daily send volume is not more than 2x your warmup peak

Sudden volume spikes trigger spam filters even on well-warmed domains

Sends are timed during business hours (Mon–Fri, 8am–6pm local time)

Sending at 3am looks automated to spam filters; business hours look human

Volume is increasing at no more than 30% per week

Faster ramp-up triggers reputation model alarms at Gmail and Outlook

Background warmup is still running during active campaigns

Stopping warmup entirely during campaigns risks reputation decay

Inbox placement is being monitored in real time

Know immediately when placement drops so you can investigate before it gets worse

Email Deliverability Checklist

Authentication

Warmup & Reputation

List Quality

Email Content

Sending Behavior

Send like the inbox is yours.