Email Marketing Metrics That Matter (and Ones to Ignore)

by Sura Hassan | Posted on

Email marketing remains one of the highest-ROI channels in digital marketing, with an average return of $42 for every dollar spent. Yet many businesses drown in email analytics, tracking dozens of metrics without understanding which ones actually drive business results. Open rates, click rates, bounce rates, unsubscribe rates, conversion rates—the list goes on. But here’s the uncomfortable truth: not all metrics are created equal, and some that marketers obsess over are almost meaningless.

The difference between effective email marketing and wasted effort often comes down to focusing on the right metrics. Metrics that predict revenue, indicate audience engagement quality, and reveal opportunities for optimization deserve your attention. Vanity metrics that look impressive in reports but don’t correlate with business outcomes? Those deserve to be ignored—or at least deprioritized dramatically.

In this comprehensive guide, we’ll cut through the noise and identify exactly which email marketing metrics you should monitor religiously and which ones you can safely ignore. We’ll explain what each metric actually tells you about your email program’s health, how to benchmark your performance, and most importantly, how to use these insights to drive real business results. By the end, you’ll know exactly where to focus your attention for maximum impact.

Why Most Email Marketers Track the Wrong Metrics

Before we dive into specific metrics, let’s address why this problem exists. Email service providers (ESPs) make it incredibly easy to track everything—dashboards overflow with data points, and reports can run dozens of pages. When everything is measured, the natural human tendency is to look at everything, giving equal weight to metrics that have vastly different business value.

The second problem is industry conditioning. For years, email marketers have been told to obsess over open rates and click-through rates as primary success indicators. These metrics became standardized benchmarks across industries, creating a situation where marketers optimize for metrics that don’t directly drive the outcomes their businesses care about—revenue, customer lifetime value, retention, and growth.

Finally, there’s the visibility issue. Some of the most important email metrics require integration with other systems—your CRM, e-commerce platform, or analytics tools. The easiest metrics to track are often the least meaningful, while the most valuable metrics require more effort to measure properly.

Why metric selection matters:

  • Limited time and resources mean you can’t optimize everything simultaneously
  • Focusing on vanity metrics creates a false sense of success while business results stagnate
  • The wrong metrics can actually lead to counterproductive optimization decisions
  • Executive stakeholders need to see metrics that connect to revenue and business objectives
  • Your email strategy should be driven by metrics that predict customer behavior and value

The Metrics That Actually Matter

Let’s start with the good news—the metrics that deserve your attention, your optimization efforts, and prominent placement in your reporting. These are the indicators that correlate with business success and provide actionable insights.

Conversion Rate: The Ultimate Success Indicator

Conversion rate measures the percentage of email recipients who complete your desired action—making a purchase, signing up for a webinar, downloading a resource, scheduling a demo, or whatever goal that specific email is designed to achieve. This is the metric that matters most because it directly ties email performance to business outcomes.

While other metrics measure engagement with the email itself, conversion rate measures whether your email actually accomplished its business purpose. An email with a 50% open rate means nothing if nobody converts. An email with a 15% open rate that drives significant conversions is successful regardless of that lower open rate.

Conversion rate should be your north star metric for campaign success. Everything else is a supporting indicator that helps you understand why conversion rate is high or low and what levers you can pull to improve it.

Why conversion rate matters most:

  • Directly measures business impact, not just email engagement
  • Connects email performance to revenue and ROI
  • Reveals whether your messaging, offer, and call-to-action are effective
  • Allows meaningful comparison between different email types and campaigns
  • Provides clear optimization targets that align with business goals

How to optimize conversion rate:

  • Ensure your call-to-action is crystal clear and compelling
  • Segment audiences so messaging is highly relevant to recipients
  • Remove friction in the conversion process (fewer form fields, simpler checkout)
  • Test different offers to find what resonates with your audience
  • Align email content with landing page experience for consistency
  • Time emails strategically based on when your audience is most likely to convert

Revenue Per Email: The ROI Reality Check

Revenue per email (also called revenue per send or revenue per recipient) divides total revenue generated from an email campaign by the number of emails delivered. This metric cuts straight to the bottom line—is this email making you money, and how much?

For e-commerce businesses, SaaS companies, or any organization where email directly drives transactions, this is arguably as important as conversion rate itself. You might have high conversion rates on low-value actions, or low conversion rates on high-value actions—revenue per email tells you which scenario is actually better for your business.

This metric also allows you to calculate customer lifetime value from email, test the financial impact of different strategies, and make investment decisions about your email program based on concrete ROI data.

Calculating and using revenue per email:

  • Total revenue attributed to email ÷ number of emails delivered = revenue per email
  • Segment by email type (promotional, automated, newsletters) to understand what drives revenue
  • Compare revenue per email against cost per email to ensure positive ROI
  • Use this metric to prioritize which email campaigns and strategies deserve more investment
  • Track over time to measure whether your email program’s financial impact is growing

Click-to-Open Rate (CTOR): True Engagement Quality

While we’ll discuss why raw click-through rate has limited value, click-to-open rate (CTOR) is actually quite useful. CTOR measures what percentage of people who opened your email actually clicked on something inside it. It removes the variable of deliverability and subject line effectiveness, focusing purely on content quality and relevance.

A high CTOR indicates that your email content is compelling to those who engage with it. A low CTOR suggests that even people interested enough to open your email aren’t finding the content valuable or relevant enough to click through. This metric helps you evaluate email content quality independent of subject line performance.

CTOR formula and benchmarks:

  • (Unique clicks ÷ unique opens) × 100 = CTOR percentage
  • Good CTOR varies by industry but typically ranges from 10-25%
  • CTOR above 20% generally indicates highly engaging content
  • Compare CTOR across campaigns to identify your most engaging content types
  • Use CTOR to test content, layout, and call-to-action effectiveness

Optimizing CTOR:

  • Make your calls-to-action visually prominent and action-oriented
  • Ensure email content is scannable with clear hierarchy
  • Deliver on the promise of your subject line—don’t create disconnect
  • Use personalization to increase relevance for recipients
  • Include multiple relevant links rather than assuming one size fits all
  • Test different content lengths and formats to find what your audience prefers

List Growth Rate: Your Pipeline Health Indicator

Your email list is a depreciating asset—people change emails, unsubscribe, or become inactive over time. List growth rate measures whether you’re growing your audience faster than you’re losing it. This metric predicts the long-term health and scalability of your email program.

A healthy list growth rate means you have sustainable lead generation and customer acquisition systems feeding your email program. Negative list growth—shrinking faster than growing—indicates serious problems with either acquisition or retention that will eventually cripple your email marketing effectiveness.

Calculating list growth rate:

  • [(New subscribers – unsubscribes – bounces) ÷ total list size] × 100 = monthly growth rate
  • Aim for 2-5% monthly growth as a healthy benchmark
  • Track this metric monthly to identify trends before they become problems
  • Segment growth rate by source to understand which acquisition channels work best

Growing your list sustainably:

  • Create compelling lead magnets that provide genuine value
  • Optimize website and landing pages with strategic email capture forms
  • Use content marketing and SEO to attract qualified subscribers
  • Implement referral programs that encourage subscribers to share
  • Ensure onboarding emails deliver value immediately to reduce early unsubscribes
  • Never buy email lists—quality always beats quantity

Email ROI: The Business Case Validator

Email marketing ROI divides the revenue generated from email by the total cost of your email program (software, personnel, design, development, and other resources). This metric proves the business value of your email investment and justifies resource allocation.

While individual campaign metrics are useful for optimization, overall email ROI demonstrates whether your email program deserves more investment, less investment, or strategic changes. It’s the metric that matters most to executives and budget decision-makers.

Calculating comprehensive email ROI:

  • (Revenue from email – total email program costs) ÷ total email program costs × 100 = ROI percentage
  • Include all costs: ESP fees, salary/contractor costs, design, development, content creation
  • Track ROI quarterly and annually to understand trends
  • Compare email ROI to other marketing channels to demonstrate relative value
  • Use ROI data to secure budget for program expansion or improvement

Engagement Over Time: The Health Score

Rather than looking at individual campaign metrics in isolation, tracking engagement patterns over time reveals crucial insights about list health and content effectiveness. Are people engaging more or less with your emails over months? Are certain segments becoming more or less engaged?

Declining engagement over time indicates content fatigue, relevance issues, or frequency problems. Improving engagement over time suggests your optimization efforts are working and your content strategy resonates.

Metrics to track over time:

  • Average engagement rate (opens + clicks) trending up or down
  • Percentage of subscribers who engaged in the last 30/60/90 days
  • Segment-level engagement trends to identify which audiences need attention
  • Active subscriber percentage (those who’ve engaged recently vs. total list)
  • Engagement patterns by subscriber tenure (do people become more or less engaged over time?)

Deliverability Rate: The Foundation Metric

None of your other metrics matter if your emails aren’t reaching inboxes. Deliverability rate measures what percentage of your sent emails actually arrive in recipient inboxes (not spam folders). This is foundational—poor deliverability undermines every other aspect of your email program.

Monitor deliverability closely and address issues immediately. Declining deliverability indicates sender reputation problems, list quality issues, or technical configuration problems that will only worsen if ignored.

Key deliverability metrics:

  • Inbox placement rate: percentage landing in inbox vs. spam
  • Bounce rate: percentage of emails that couldn’t be delivered (should be under 2%)
  • Spam complaint rate: percentage of recipients marking as spam (should be under 0.1%)
  • Unsubscribe rate: percentage opting out (typically 0.2-0.5% per campaign)

Maintaining strong deliverability:

  • Authenticate your sending domain with SPF, DKIM, and DMARC
  • Maintain clean email lists by removing hard bounces and inactive subscribers
  • Never purchase email lists or send unsolicited emails
  • Monitor sender reputation through tools like Google Postmaster or Microsoft SNDS
  • Send consistently—erratic sending patterns can harm reputation
  • Make unsubscribing easy to reduce spam complaints

The Metrics You Can (Mostly) Ignore

Now for the controversial part—metrics that dominate email marketing discussions but provide limited actionable value. This doesn’t mean these metrics are completely useless, but they’re drastically over-emphasized relative to their actual business importance.

Open Rate: The Increasingly Meaningless Metric

Email open rate used to be a valuable metric, measuring the percentage of recipients who opened your email. It indicated subject line effectiveness and general audience interest. Then Apple’s Mail Privacy Protection came along and changed everything.

With iOS 15 and later, Apple Mail (which represents roughly 40-50% of email opens) now pre-loads images and content, which triggers open tracking pixels even if the human recipient never actually opened the email. This means open rates are artificially inflated and increasingly unreliable as a true engagement indicator.

Beyond the privacy protection issue, open rates were always an imperfect metric. They measure subject line effectiveness but say nothing about whether email content was valuable. An attention-grabbing clickbait subject line might generate high opens but terrible engagement and conversions.

Why open rate matters less than you think:

  • Apple Mail Privacy Protection makes opens increasingly unreliable
  • Opens don’t correlate strongly with conversions or business outcomes
  • Subject line effectiveness doesn’t predict email program success
  • Opens can be easily manipulated with sensationalist subject lines
  • The metric measures curiosity, not value delivery or business impact

What to do instead: Focus on CTOR (click-to-open rate) instead of raw open rate. CTOR measures engagement quality among those who opened, removing some of the unreliability. Better yet, focus primarily on conversion rate and revenue metrics that directly measure business impact.

Raw Click-Through Rate: The Misleading Engagement Metric

Click-through rate (CTR) measures what percentage of all email recipients clicked a link. While this seems like a useful engagement metric, it has significant limitations. CTR combines subject line effectiveness (whether people opened) with content effectiveness (whether people clicked), making it hard to diagnose what’s actually working or not working.

More problematically, raw CTR doesn’t distinguish between engaged clicks and accidental clicks, doesn’t measure click quality, and doesn’t indicate whether those clicks led to valuable outcomes. A high CTR on unqualified traffic is less valuable than a lower CTR on highly qualified, conversion-ready clicks.

CTR limitations:

  • Mixes two different performance factors (opens and clicks) into one metric
  • Doesn’t measure click quality or whether clicks led to conversions
  • Can be artificially inflated by including multiple links or unsubscribe clicks
  • Varies wildly by email type making benchmarking difficult
  • Doesn’t directly predict business outcomes

What to track instead: Focus on CTOR (click-to-open rate) to measure content engagement quality, and conversion rate to measure whether clicks resulted in valuable outcomes. If you track CTR at all, use it as a secondary supporting metric, not a primary success indicator.

Unsubscribe Rate (Within Reason): The Misunderstood Metric

Every email marketer fears unsubscribes, treating them like personal rejections. The reality? A healthy unsubscribe rate (typically 0.2-0.5% per campaign) is completely normal and even desirable. People unsubscribe because they’re no longer in your target market, they changed jobs, their needs changed, or they receive too much email generally.

Unsubscribes actually improve your list quality by removing disengaged people who would never convert anyway. They’re self-selecting out, improving your engagement rates and deliverability. Obsessing over keeping unsubscribe rates as low as possible can lead to bland, inoffensive content that doesn’t resonate strongly with your ideal customers.

Healthy perspective on unsubscribes:

  • Unsubscribe rates of 0.2-0.5% are normal and acceptable
  • People unsubscribing aren’t your ideal customers anyway
  • A clean, engaged list is more valuable than a large, disengaged list
  • Unsubscribes are preferable to spam complaints or inactive subscribers
  • Slightly higher unsubscribe rates with better engagement among remaining subscribers is a net positive

When to worry about unsubscribes: If your unsubscribe rate suddenly spikes (above 1%) or trends consistently upward, that indicates a real problem—frequency issues, relevance problems, or content quality decline. Monitor the trend, not individual campaign fluctuations.

Time-Based Metrics: Interesting But Not Actionable

Metrics like “best time to send emails” or “average time to open” generate interesting reports but rarely provide actionable insights. The reality is that optimal send times vary dramatically by audience, and most email service providers now offer send-time optimization that handles this automatically.

Similarly, metrics about how long people spend reading emails or when they click don’t typically lead to meaningful optimization opportunities. Focus your analytical energy on metrics that suggest clear actions to improve results.

Time-based metrics with limited value:

  • Best day of week to send (highly audience-dependent, often inconclusive)
  • Best time of day to send (varies by audience, automated optimization handles this)
  • Average time to open after sending (doesn’t predict conversion likelihood)
  • Time spent reading email (difficult to measure accurately, unclear optimization path)

Forwarding Rate: The Vanity Metric

Email forwarding rates measure how often recipients forward your email to someone else. This sounds valuable—earned distribution and word-of-mouth recommendation. In reality, email forwarding is incredibly rare (typically well under 1%), difficult to track accurately, and doesn’t strongly correlate with business outcomes.

Most sharing today happens on social media, through messaging apps, or via direct links rather than email forwarding. Tracking forwarding rates and trying to optimize them is usually wasted effort compared to focusing on conversion optimization and revenue metrics.

Why forwarding rate doesn’t matter much:

  • Forwarding is rare in modern email behavior
  • Difficult to track accurately (many forwards aren’t measurable)
  • Doesn’t strongly predict business value or campaign success
  • Optimizing for forwarding rarely improves more important metrics
  • Social sharing and direct links have largely replaced email forwarding

How to Structure Your Email Marketing Dashboard

Knowing which metrics matter is only useful if you actually monitor them consistently. Here’s how to structure an effective email marketing dashboard that keeps you focused on what matters.

The Executive Dashboard: Three Key Metrics

For leadership and stakeholders who need the big picture without getting lost in details, report three primary metrics monthly or quarterly:

  1. Email Marketing ROI: Shows the business value of email investment
  2. Revenue from Email: Demonstrates contribution to company revenue
  3. List Growth Rate: Indicates pipeline health and program sustainability

These three metrics tell the entire story of email program health and business impact without requiring deep email marketing expertise to interpret.

The Optimization Dashboard: Campaign Performance

For marketing teams actively managing campaigns, create a dashboard that reveals optimization opportunities:

Per-Campaign Metrics:

  • Conversion rate (primary success metric)
  • Revenue per email sent
  • Click-to-open rate (CTOR)
  • Deliverability rate
  • Active subscriber engagement rate

Trend Metrics (tracked over time):

  • Month-over-month list growth
  • Average engagement rate trends
  • Deliverability trends
  • Revenue per subscriber trends

The Diagnostic Dashboard: Problem Identification

Create a separate dashboard specifically for identifying problems before they become serious:

Health Indicators:

  • Hard bounce rate (flag if above 2%)
  • Spam complaint rate (flag if above 0.1%)
  • Unsubscribe rate trends (flag if consistently increasing)
  • Percentage of list that hasn’t engaged in 90+ days
  • Sender reputation scores from major ISPs

This diagnostic view helps you catch deliverability issues, list quality problems, or engagement decline early when they’re easier to fix.

Benchmarking: What Good Looks Like

Understanding metrics is meaningless without context. Here are realistic benchmarks across industries to help you evaluate your performance.

General Email Marketing Benchmarks (2024-2025):

  • Conversion rate: 1-5% (varies dramatically by industry and definition of conversion)
  • Click-to-open rate: 10-25%
  • Deliverability rate: 95-99% (anything below 95% needs immediate attention)
  • List growth rate: 2-5% monthly
  • Bounce rate: Under 2%
  • Unsubscribe rate: 0.2-0.5% per campaign
  • Spam complaint rate: Under 0.1%

Industry-Specific Considerations:

  • E-commerce typically sees higher conversion rates but lower CTOR than B2B
  • B2B generally has longer sales cycles, so immediate conversion rates are lower
  • Media and publishing see higher engagement rates but lower direct revenue per email
  • Nonprofit organizations often see higher open engagement but lower purchase conversion

Important: Benchmarks provide general context, but your own historical performance is the most meaningful comparison. Aim to improve your metrics over time rather than obsessing over how you compare to industry averages.

Taking Action: From Metrics to Optimization

Measuring the right metrics is only valuable if you use those insights to improve performance. Here’s how to turn your metric monitoring into continuous optimization.

Monthly Optimization Cycle:

  1. Review your key metrics against previous periods and goals
  2. Identify the biggest opportunity area (lowest conversion rate segment, declining engagement, etc.)
  3. Develop hypothesis for improvement (better segmentation, different offer, new content approach)
  4. Implement A/B tests to validate hypothesis
  5. Analyze results and scale what works
  6. Document learnings and move to next opportunity

Quarterly Strategic Review:

  • Assess overall email ROI and growth trends
  • Evaluate list health and deliverability
  • Review segment performance to identify underserved audiences
  • Analyze revenue contribution by email type (promotional, triggered, nurture)
  • Plan strategic initiatives based on data insights

The brands that win with email marketing aren’t those tracking the most metrics—they’re those focusing on the right metrics and relentlessly optimizing based on those insights.

The Bottom Line: Focus on What Drives Business Results

Email marketing metrics should serve your business goals, not become goals themselves. The difference between email programs that drive significant ROI and those that simply “check the box” on email comes down to metric focus. Track what matters, ignore what doesn’t, and spend your optimization energy on activities that actually move the needle on conversion and revenue.

Open rates don’t pay the bills. Click-through rates don’t fund your business. Conversion rates, revenue per email, and overall ROI—these are the metrics that prove email marketing’s value and guide you toward increasingly effective strategies.

At DECODINGLEADS, we build email marketing strategies around metrics that matter. We focus on business outcomes, not vanity metrics that look good in reports but don’t drive growth. Our approach combines strategic segmentation, compelling content, and relentless optimization focused on conversion and revenue—because those are the metrics that actually matter for your business.

Ready to build an email marketing program that focuses on metrics that drive real business results? Contact DECODINGLEADS today to discuss how our email marketing services can help you increase conversion rates, improve ROI, and build a sustainable, revenue-generating email program. Let’s focus on what actually matters.

The best email marketers don’t track everything—they track what drives business results and optimize relentlessly.