How to Stop Email Tracking: Pixels, Read Receipts and More
Every time you open a marketing email, there's a reasonable chance the sender knows about it within seconds. Not because of any special access to your account, but because of a tiny invisible image called a tracking pixel — a 1x1 transparent GIF embedded in the email body. When your email client loads that image, it makes a network request that tells the sender exactly when you opened it, where you are, and what device you used.
What tracking pixels reveal
A single open on a marketing email can reveal:
- Open confirmation — the email was opened (not just delivered)
- Timestamp — exact date and time, down to the second
- IP address — which can be geolocated to city level
- Device type — mobile or desktop, operating system, email client
- Repeat opens — how many times you've viewed the email
This data flows directly into CRM and marketing automation systems. Sales teams use open data to time follow-up calls ("they opened our email 5 minutes ago — call them now"). Marketing teams use open rates to segment mailing lists and personalise campaigns. Your reading behaviour is a product that marketers are selling to improve their targeting of you.
How to block tracking pixels by email client
Apple Mail (iOS & macOS)
Apple introduced Mail Privacy Protection in iOS 15 and macOS Monterey (2021). When enabled, Apple proxies all image requests through its servers and pre-loads them — meaning the sender sees Apple's server opening the email, not your actual location and timing.
Enable it: Settings → Mail → Privacy Protection → toggle "Protect Mail Activity" on. On macOS: Mail → Settings → Privacy → enable "Protect Mail Activity."
This is the most comprehensive built-in protection available — it doesn't just block pixels, it actively misleads trackers.
Gmail
Gmail proxies external images through Google's servers by default. This means the sender sees a Google IP address, not yours. However, it doesn't prevent the open-time signal — Google still loads the pixel, just from its servers. The sender still knows you opened the email; they just don't get your real IP.
To block images entirely: Settings (gear icon) → See all settings → General → Images → "Ask before displaying external images." This prevents pixels from loading at all, at the cost of images not displaying.
Outlook (desktop)
Outlook blocks external images by default in many configurations. Check: File → Options → Trust Center → Trust Center Settings → Automatic Download → enable "Don't download pictures automatically." Images won't display unless you click "Download Pictures" on each email — but tracking pixels won't load either.
Dedicated tracking blockers
Browser extensions and apps specifically designed to block email tracking:
- Hey Email — strips tracking pixels before delivery (paid email service)
- Ugly Email — Chrome extension that marks tracked emails with an eye icon in Gmail
- Mailtrack.io blocker — blocks Mailtrack-based pixels specifically
- StoP (Gmail extension) — detects and blocks common tracking pixels
UK legal context: are tracking pixels legal?
Tracking pixels in marketing emails are subject to UK GDPR because they process personal data (your IP address and behaviour). Under UK GDPR:
- The use of tracking pixels must be disclosed in the organisation's privacy policy
- Processing your data through tracking requires a lawful basis — usually legitimate interest for analytics
- You can object to this processing under UK GDPR Article 21
In practice, enforcement against individual tracking pixel use is minimal. The ICO has focused more on large-scale consent violations. But the underlying data processing is subject to UK GDPR, and privacy-respecting senders should disclose their tracking practices.
The bigger picture: combining tools
Blocking tracking pixels addresses what happens after you receive an email. But the most effective protection is avoiding the marketing list in the first place:
- Use disposable email for sign-ups to sites that will send marketing — no real address means no tracking
- Enable Apple Mail Privacy Protection or Gmail's image proxying for emails that do reach your real address
- Unsubscribe from email lists you no longer want to receive (from recognised senders only)
The best protection against email tracking starts before the first email is sent. Use a disposable address.
Get a Free Disposable Email