MailSentinel vs Postmark DMARC: Free vs Full-Featured

Postmark's Free DMARC Monitoring

Postmark (by ActiveCampaign) is primarily an email delivery service, but they offer a completely free DMARC monitoring tool. It's a generous offering that helps many organizations get started with DMARC.

What Postmark DMARC Offers

• Free DMARC aggregate report parsing
• Weekly email digest of your authentication status
• Basic visualization of sending sources
• No account required (just email)
• DNS record generator tools

The Postmark DMARC Value Proposition

Postmark provides this free service to:

1. Promote DMARC adoption
2. Build goodwill in the email community
3. Introduce users to their paid email service

It's genuinely useful, with no strings attached.

When Free Is Enough

Postmark's free DMARC tool may be all you need if:

✅ You're Just Starting Out

If you're new to DMARC and want to:

• Understand what's being sent from your domain
• Get familiar with DMARC reports
• Build a case for more investment

Postmark's free tool provides valuable initial insight.

✅ You Have Simple Email Infrastructure

If you:

• Send email from one or two services
• Have low email volume
• Don't require immediate alerts
• Can wait for weekly summaries

✅ Budget Is Truly Zero

Some organizations genuinely have no budget for security tools. Free is better than nothing.

When You Need More

Postmark's free tier has significant limitations:

Weekly Reports Only

Postmark: Sends a digest once per week.

MailSentinel: Real-time dashboard and alerts.

Why it matters: Authentication failures, spoofing attempts, or misconfigurations can go undetected for days. By the time you see your weekly report, the damage may be done.

No Real-Time Alerts

Postmark: No alerting capability.

MailSentinel: Configurable alerts via email, Slack, webhooks.

Why it matters: If someone starts spoofing your domain or a legitimate service breaks authentication, you want to know immediately.

No SPF/DKIM Monitoring

Postmark: Only parses DMARC aggregate reports.

MailSentinel: Monitors your actual SPF and DKIM DNS records.

Why it matters: Issues with your SPF record (like exceeding 10 lookups) or DKIM keys (like weak keys or missing selectors) aren't caught by Postmark.

No Historical Data

Postmark: Limited data retention.

MailSentinel: Full historical trends and analysis.

Why it matters: Understanding trends over time is crucial for detecting gradual changes or proving compliance.

No Team Features

Postmark: Single email recipient.

MailSentinel: Multiple users, roles, shared dashboards.

Why it matters: Security is a team effort. Shared visibility improves response.

Feature Comparison Table

The Upgrade Path

Many MailSentinel customers started with Postmark's free tool. The typical journey:

Stage 1: Postmark (Free)

• Set up DMARC for the first time
• Understand your sending sources
• Get weekly visibility

Stage 2: Realize Limitations

• Miss an authentication issue between weekly reports
• Want to share access with team members
• Need to respond faster to problems

Stage 3: MailSentinel (Paid)

• Upgrade to real-time monitoring
• Add team collaboration
• Get proactive alerts

Migrating from Postmark to MailSentinel

The process is simple since DMARC supports multiple RUA addresses:

Step 1: Add MailSentinel

Update your DMARC record to include both:

v=DMARC1; p=quarantine; rua=mailto:abc123@dmarc.postmarkapp.com, mailto:yourid@reports.mailsentinel.io

Step 2: Compare Side-by-Side

Run both for a couple of weeks. You'll likely notice:

• MailSentinel updates in real-time vs. weekly
• More detailed source identification
• SPF/DKIM status you weren't seeing before

Step 3: Remove Postmark (Optional)

Once you're confident, you can remove Postmark from your RUA—or keep it as a backup.

Pricing Perspective

Is $14/Month Worth It?

Consider what you're getting:

For most organizations, the cost of a single email incident—reputation damage, deliverability issues, phishing success—far exceeds $14/month.

Free + Paid Hybrid

Some users keep Postmark as a free backup:

• Postmark for weekly summary review
• MailSentinel for daily operations and alerts

This redundancy costs nothing extra.

Use Case Scenarios

Scenario 1: Personal Domain

"I use Postmark for my personal domain. It's just me, low volume, and I check the weekly digest. Free is perfect."

Verdict: Postmark is probably fine.

Scenario 2: Small Business

"We have 50 employees and send transactional emails. When our DKIM broke, Postmark didn't tell us for 5 days. Now we use MailSentinel for instant alerts."

Verdict: MailSentinel's real-time monitoring is worth it.

Scenario 3: Security-Conscious Startup

"Even before we had any incidents, we knew we needed real-time visibility. You can't react to weekly reports in security."

Verdict: Start with MailSentinel from day one.

Summary

Start Your Real-Time Monitoring

Graduate from weekly digests to real-time visibility. MailSentinel's 14-day free trial lets you experience the difference.

Start Free Trial →