Email service providers offer extensive tracking capabilities. While these features help marketers measure campaign performance, privacy regulations create strict boundaries around what data you can collect and retain. Understanding how to navigate these requirements helps build a tracking strategy that respects subscriber privacy while meeting legitimate business needs.
Core Tracking Metrics
Most email programs focus on three primary metrics. Open tracking attempts to measure message views through tracking pixels. However, modern email clients either block these pixels automatically or load them without user action, making open data increasingly unreliable for decision-making.
Click tracking provides stronger engagement signals by routing subscribers through redirect URLs before reaching content. This introduces important questions about data collection scope and retention periods that need careful consideration in your privacy strategy.
Conversion tracking connects email engagement to website actions. While valuable for ROI calculations, tracking users across multiple systems requires extra scrutiny under privacy regulations. You’ll need to document both the business justification and appropriate safeguards.
Privacy Requirements
Start with a Data Protection Impact Assessment (DPIA). Even if not explicitly required by your local regulations, a DPIA helps catalog and justify your data processing activities. The process forces you to examine what you collect and why.
Your subscriber list contains basic data for sending mail – names, email addresses, and preferences. But many programs collect additional demographic data that may not serve a clear purpose. If you never segment by zip code, storing it creates an unnecessary privacy risk.
Campaign engagement data tracks message opens and clicks. While you need this for effectiveness measurement, storing it forever likely exceeds legitimate business requirements. Consider setting retention limits that align with your reporting cycles.
Website interaction records show post-click behavior. Again, this serves clear ROI calculation needs. However, tracking individuals across multiple systems introduces extra privacy considerations. In many cases, aggregate data could serve the same purpose with less risk.
ESP Platform Limitations
At best, your email service provider probably offers just three levels of tracking controls: account settings control tracking platform-wide as your defaults, domain settings let you configure tracking separately for each sending domain, and send settings allow you to turn off tracking for one particular job.
That’s it. No list-level controls. No subscriber-level settings. No geographic options. No consent-based tracking rules. This creates problems when subscribers request minimal tracking since you can’t simply flip a switch. Instead, you must route their mail through a some hacked-together process (usually a dedicated segment matched with a job or set of jobs) with restricted tracking enabled.
If you can handle things using sending domain settings, this limitation still cascades into other challenges. Each domain needs its own suppression list maintenance – unsubscribes from one domain may not automatically apply to others.1 Authentication records multiply since every sending domain needs its own SPF, DKIM and DMARC setup. Reporting gets messy when you need to combine data across domains manually.
What To Do
Start with that DPIA. You need to know exactly what data you collect, why you’re collecting it, and what difference it should be making for you. Many marketing teams discover they gather far more information than they use for decision-making.
Once you understand your current state, examine your ESP’s features carefully. These vary significantly between platforms. Having a clear picture of what you can and cannot control helps set realistic expectations with stakeholders.
Document your tracking configurations, data retention rules, and reporting processes. When privacy regulators, auditors, or even your ESP’s abuse and compliance team come knocking, you’ll appreciate having clear records of your decisions and justifications.
Keep monitoring as conditions evolve. ESP platform offerings change. Privacy regulations shift. Your business needs transform. What works today might not work tomorrow. Build regular reviews into your process.
Perfect tracking isn’t the goal. Focus on gathering enough reliable data to make solid business decisions while respecting subscriber privacy. Sometimes that means accepting you can’t measure everything you might want to measure.
Footnotes
- Mickey Chandler, Make It Easy To Leave, Spamtacular (Jan. 17, 2025), https://www.spamtacular.com/2025/01/17/make-it-easy-to-leave/ (last visited Jan 23, 2025). ↩︎
