What Is Email Masking? Plus Addressing, Aliases, and Other Privacy Tricks

Email masking is a privacy technique that hides your real email address behind a proxy address, forwarding incoming messages to your actual inbox while keeping your identity hidden from senders. Common email masking methods include Gmail plus addressing, dedicated alias services like SimpleLogin and addy.io, Apple's Hide My Email, and disposable temporary email from services like TempEmailInbox. Each method offers different levels of privacy, persistence, and protection against data breaches and spam.

Email Masking Explained

Email masking is a broad term for any technique that hides your real email address behind a proxy address. When someone sends mail to the proxy address, it gets forwarded to your real inbox. The sender never sees your actual email address. If the proxy address starts receiving spam or gets leaked in a breach, you simply disable or delete it. Your real address stays private and unaffected.

The concept is simple, but implementations vary widely. Some email masking solutions are built into your existing email provider, some are standalone services, and some are integrated into your operating system or browser. Let us walk through each one.

Gmail Plus Addressing (The Free Trick)

If you have a Gmail address, you can add a plus sign (+) followed by any text before the @ symbol, and the email will still arrive in your inbox. For example, if your email is [email protected], you can use [email protected], [email protected], or [email protected]. All of these deliver to [email protected].

Advantages

• Completely free, no setup required.
• Works with any Gmail account immediately.
• Unlimited variations, you can create a unique address for every service.
• Makes it easy to create email filters. You can automatically label or archive emails sent to specific plus addresses.
• Helps you identify which service sold or leaked your email. If you gave [email protected] only to Acme Store and start getting spam there, you know exactly who is responsible.

Limitations

• Trivially easy to strip: Anyone can see that [email protected] maps to [email protected]. Data brokers and spammers routinely strip the plus portion to extract the base address. This means it offers zero protection against determined data collectors, as the Electronic Frontier Foundation has noted in their research on email surveillance.
• Some services reject it: A surprising number of websites consider the + character invalid in email addresses, even though it is technically legal per RFC 5321. You will encounter registration forms that reject plus addresses entirely.
• No protection from your provider: Google still sees all the emails. Plus addressing does not add any encryption or prevent Google from processing your email content.
• Cannot disable individual addresses: If [email protected] starts getting spam, you cannot stop it without creating a filter to auto-delete those messages. There is no "off switch" for a specific plus address.

Email Alias Services

Email alias services generate unique proxy addresses that forward to your real inbox. Unlike plus addressing, these proxy addresses are completely different domains that do not reveal your real email. If a service sees only the alias, there is no way to reverse-engineer your actual address.

SimpleLogin

SimpleLogin (now owned by Proton) is one of the most popular email alias services. It generates random addresses like [email protected] that forward to your real email. You can reply through the alias, so the conversation stays masked in both directions. SimpleLogin offers browser extensions and mobile apps that auto-suggest new aliases when you encounter email signup forms.

The free tier provides 10 aliases. The premium plan (included with Proton Unlimited at $9.99/month) offers unlimited aliases, custom domains, and the ability to use your own domain for aliases. SimpleLogin integrates directly with ProtonMail for the smoothest experience, but works with any email provider.

addy.io (formerly AnonAddy)

addy.io is an open-source email alias service that offers a more generous free tier than SimpleLogin. The free plan includes unlimited standard aliases (on shared domains) and allows you to reply anonymously through aliases. You can also self-host addy.io if you prefer to control the infrastructure entirely.

addy.io's unique feature is catch-all aliases on custom domains. If you own a domain like mydomain.com, you can create aliases on the fly by using any address at that domain ([email protected], [email protected]) without pre-registering them. The paid plans start at $1/month, making it one of the most affordable alias services.

Firefox Relay

Mozilla's Firefox Relay integrates directly into the Firefox browser. When you encounter an email field on a website, Relay offers to generate a masked address for you. Emails sent to the masked address are forwarded to your real inbox. The free tier provides 5 aliases, and the premium plan ($1.99/month) offers unlimited aliases and a phone number mask.

Firefox Relay's strength is its seamless browser integration, which makes it practical for people who do not want to manage a separate service. Its weakness is that it only works within the Firefox ecosystem, and the free tier's 5-alias limit is quite restrictive.

Advantages of Alias Services (General)

• Real privacy: the alias does not reveal your actual email address.
• You can disable individual aliases if they start getting spam.
• Bidirectional masking: you can reply through the alias without exposing your real address.
• Persistent: aliases keep working as long as you maintain the service.
• Great for long-term accounts where you want ongoing privacy.

Limitations of Alias Services

• Single point of failure: if the alias service goes down or shuts down, all your aliases stop working. This is a real risk with smaller services.
• The alias service can read your forwarded emails (unless using encrypted providers like ProtonMail with SimpleLogin).
• Free tiers are limited. For serious use, expect to pay $1-10/month.
• Some websites block known alias service domains, similar to how they block disposable email domains.

Apple's Hide My Email

Apple's Hide My Email feature, included with iCloud+ ($0.99/month and up) and Apple One subscriptions, generates unique random addresses like [email protected]. These addresses forward to your Apple ID email. You can create them when signing up for services through Safari, Mail, or the "Sign in with Apple" flow.

Advantages

• Deep integration with Apple's ecosystem: works natively in Safari, Mail, and Sign in with Apple.
• Unlimited aliases with any iCloud+ subscription.
• Backed by Apple's privacy reputation and infrastructure. Unlikely to shut down.
• Aliases can be individually deactivated.
• Works with iCloud custom domains, so aliases can use your own domain.

Limitations

• Apple ecosystem only. No browser extensions for Chrome, Firefox, or Windows.
• Requires an iCloud+ subscription (minimum $0.99/month).
• The generated addresses are obviously Apple relay addresses, which some services may block.
• You trust Apple with your email forwarding. If Apple's policies change, your privacy guarantee changes with them.

Disposable Temporary Email

Disposable temp mail services like TempEmailInbox take a fundamentally different approach. Instead of creating a forwarding proxy to your real inbox, they provide a completely separate temporary inbox with no connection to your real email at all. You visit the service, get an instant email address, use it for whatever you need, and the inbox expires after a set period (typically 10 minutes to 24 hours, depending on the service).

Advantages

• Zero connection to your identity: No account creation, no forwarding to your real email, no data link between the temp address and you. This approach aligns with privacy-by-design principles outlined in the NIST Privacy Framework.
• Instant and free: No signup, no subscription, no configuration. Visit the site and get an address in seconds.
• Self-cleaning: Inboxes expire automatically. No cleanup, no management, no accumulating aliases to keep track of.
• Perfect for one-time interactions: Downloading a whitepaper, registering for a one-time event, testing a service, verifying a signup.
• No trust required: Since the inbox is not connected to your real email, even if the temp mail provider is compromised, your identity remains protected.

Limitations

• Temporary by design: Once the inbox expires, you lose access. Not suitable for accounts you want to keep long-term.
• Cannot send or reply: Most temp mail services are receive-only. You cannot send outgoing emails from the disposable address.
• Blocked by some services: Major platforms (Google, Facebook, Instagram) maintain blocklists of known disposable email domains.
• Public inboxes on some providers: Some free temp mail services have public inboxes where anyone who knows the address can read the messages. TempEmailInbox generates unique addresses to mitigate this, but it is worth being aware of the risk on other services.

Which Method Should You Use?

The right choice depends on your specific situation. Here is a practical decision framework.

Use Plus Addressing When...

• You just want to organize incoming email with filters.
• You want a quick way to identify which service leaked your email.
• The service you are signing up for rejects alias domains and temp mail domains.
• You do not care if the service knows your real email, just want tracking visibility.

Use an Email Alias Service When...

• You are creating an account you plan to use regularly and want ongoing privacy.
• You need to reply from the masked address (bidirectional communication).
• You want the option to disable a specific address later without losing others.
• You are comfortable paying for a subscription and trusting a third-party service.

Use Apple Hide My Email When...

• You are already in the Apple ecosystem with an iCloud+ subscription.
• You primarily browse with Safari on Apple devices.
• You want a "set it and forget it" solution with no third-party services to manage.
• You use Sign in with Apple frequently.

Use Temporary Email (TempEmailInbox) When...

• You need a one-time email address with zero commitment.
• You are downloading something that requires an email but offers no ongoing value.
• You are testing a new service and do not want to commit your real email.
• You want maximum anonymity with no account creation and no connection to your identity.
• You are a developer testing email flows (registration, password reset, notifications).

Your email address is your digital identity. Protect it the same way you protect your physical address: share the real one only with people and organizations you trust, and use a proxy for everything else. Start with a free temporary email from TempEmailInbox for your next signup, and experience the difference privacy makes.

Frequently Asked Questions