Email alias services generate per-service email addresses pointing back to a hidden real inbox. Major options: SimpleLogin (Proton-owned, $36/year for unlimited aliases), Addy.io (formerly AnonAddy, $12/year basic tier), Firefox Relay (Mozilla, free with limits, $1/month for unlimited), DuckDuckGo Email Protection (free, requires Duck account). Lets a single service breach compromise one alias instead of the master address.
What it means in practice
The structural value of aliases is breach containment. When LinkedIn was breached, every user whose primary email was their LinkedIn registration email had that email exposed across the breach corpus, joined to a hashed (often crackable) password and a job history. With aliases, the LinkedIn breach exposes a single-purpose alias that the user can disable in seconds, and the rest of the user’s account ecosystem remains untouched. The marginal cost is small (a few dollars a year and a slight inconvenience setting up new accounts); the cumulative protection over years of breach exposure is significant. Aliases also break the cross-site advertising-tracking heuristic that uses email-as-identifier (LiveRamp’s ATS, the Trade Desk’s UID2.0); each service sees a different alias and cannot correlate.
Who uses them, and how
Used by: privacy-conscious individuals reducing breach exposure, journalists protecting source-contact email addresses from breach correlation, lawyers compartmenting client-matter communications, and increasingly mainstream users who installed 1Password or Proton Pass and discovered the alias-generation feature. The alias services differentiate on jurisdiction (SimpleLogin in France under Proton ownership, Addy.io in the UK, Firefox Relay in the US under Mozilla), pricing, and feature set (custom domains for personal aliases, attachment forwarding, sender filtering). For most users, any of the four works; the choice is between Proton-stack consolidation, Mozilla’s nonprofit ownership, or DuckDuckGo’s free tier.
What you can change today
Sign up for one alias service (SimpleLogin and Addy.io both have free tiers worth trying). Generate aliases for the next 10 services you sign up for; do not migrate existing accounts immediately (the cost-benefit of mass migration is poor; the cost-benefit of new-account aliasing is excellent). For the highest-value 5 existing accounts (primary email, password manager, financial accounts, social media that hosts your audience, cloud storage), switch the registered email to an alias and update the recovery email accordingly; if any of these is breached, the alias absorbs the damage. Over a year of new signups, the alias coverage compounds without major migration effort.