The playbook for email success keeps evolving. Privacy shifts, AI-assisted tooling, and tougher inbox rules mean the KPIs that mattered in 2022 aren’t the whole story in 2025.This guide keeps it simple: measure what matters—deliverability, real engagement, and revenue—and use those numbers to make better sends, every time.
Think of deliverability as your programme’s credit score—earned over time and easily damaged if list quality slips. In 2024–2025, inbox providers tightened the rules for bulk senders, so keeping that score healthy is critical.
The rules: Gmail and Yahoo now require senders to authenticate messages (SPF, DKIM, and DMARC for bulk volumes), keep spam complaint rates low, and include a one-click unsubscribe in marketing or promotional emails. Gmail treats you as a bulk sender if you send about 5,000 or more messages a day to @gmail addresses. Transactional messages are exempt from the one-click unsubscribe requirement.
Key limits to monitor
Pro Tip: Set alerts in your email service provider (ESP) and Gmail Postmaster so you’re notified if bounce or spam complaint rates rise. Early fixes protect your sender reputation.
Open rate still has value for spotting trends, but in 2025 it’s no longer a reliable primary metric. Apple Mail Privacy Protection (MPP) automatically preloads tracking pixels, meaning many “opens” are generated by the system rather than a person reading your email. Litmus estimates that more than half of all opens now happen on MPP-enabled devices, inflating open rates for every sender.
The focus: Click-based metrics give a truer picture:
2025 reality check: MailerLite’s latest dataset (3.3M+ campaigns) shows: Open 42.35%, CTR 2.00%, CTOR 5.63%, Unsub 0.08%. Treat open rate as a rough guide; clicks are the firmer signal. For sector-specific email marketing benchmarks, Mailchimp publishes industry-by-industry tables covering everything from government to ecommerce.
Review your link map: Are most clicks going to your main call-to-action (CTA), or are they scattered across less important links? A focused design and clear hierarchy will guide readers to the right action.
Pro Tip: If CTR is steady but CTOR is dropping, your subject line and preview are enticing opens but the content isn’t delivering on the promise. Align the “promise” with the “payload” and keep your main CTA visible without scrolling.
Vanity metrics don’t pay invoices. To connect your email activity directly to business results, focus on two simple KPIs:
Track RPE and RPS on rolling 30–90 day windows. This smooths out short-term campaign spikes and shows whether segmentation, offers, and list quality are compounding over time.
Before changing creative, test the Offer × Audience fit. Even the best copy can’t save a mismatch between what you’re offering and who you’re sending it to.
Pro Tip: Maintain a 90-day RPS cohort for each segment. It will reveal which audiences are responding to your nurture efforts—and where list quality or offer alignment may be holding you back.
These are the core email KPI formulas to standardise across campaigns:
When benchmarking, compare like-for-like—newsletter vs. promo, single CTA vs. multiple links, etc. MailerLite’s analysis of Apple MPP inflation is a reminder to rely more on CTR and CTOR than opens when judging creative performance.
Privacy-first measurement in 2025
Apple Mail Privacy Protection hides whether and when a subscriber opened your email, inflating open rates. More than half of opens now occur on MPP-enabled devices. To get a true performance picture:
For plain-language email marketing metrics definitions, Mailchimp’s help centre is a good reference.
Healthy delivery starts with a clean list. Email Hippo identifies invalid and risky addresses before you hit send, helping you keep bounces and complaints low. That protects your deliverability “credit score” over time and gives your content a fair chance to work.
When in doubt, ask: Does this metric help me send better emails?
If your email marketing KPIs align with subscriber experience—relevance, timing, and clarity—the results will follow.
Join the conversation: Which KPIs are you watching most in 2025? Share your approach—or validate a sample list of up to 100 for free when you sign up for Email Hippo CORE and see how list quality shifts your metrics.
What is a KPI in email marketing?
A KPI is a measurable indicator that shows whether your email programme is achieving its objectives—deliverability, engagement, and revenue.
Which KPIs matter most in 2025?
Focus on deliverability (hard bounces, spam complaints), engagement (CTR, CTOR), and outcomes (conversion rate, revenue per email and per subscriber).
Should I still trust open rate in 2025?
Use it only as a trend guide. Apple Mail Privacy Protection inflates opens, so rely more on clicks and conversions.
What’s a good CTR and CTOR?
On average, CTR is ~2% and CTOR ~5–6% across industries. Always benchmark against your own past results.
What’s an acceptable hard bounce rate?
Keep it under 2%. Anything higher signals list quality issues and the need for validation.