What is Shield and when should you use it?
Shield is an extra layer of protection that sits on top of your email aliases. While filters and spam scoring evaluate the content of messages, Shield controls the flow — how many emails are allowed, when they're delivered, and from whom.
Three Shield features
Shield consists of three independent features that you can enable separately on any alias:
| Feature | What it controls | Best for |
|---|---|---|
| Rate Limiter | How many emails per time period | Aliases used on high-volume services, online shopping, forums |
| Delivery Snoozer | When emails are delivered | Work aliases outside business hours, focus time, weekends |
| Gatekeeper | Who can send to this alias | Sensitive aliases shared only with trusted contacts |
Each feature can be used independently or combined. For example, you could enable both a rate limiter and gatekeeper on the same alias for maximum protection.
When should you use Shield?
Rate Limiter
Use the rate limiter when an alias receives more email than you want to deal with. Typical scenarios:
- You signed up for a shopping site that sends daily promotional emails
- A forum sends notification emails for every reply in a thread
- A service sends hourly status updates that you only need once a day
Delivery Snoozer
Use the snoozer when you want to separate work and personal time:
- Work alias: deliver only Monday–Friday 8:00–18:00
- Newsletter alias: deliver only on weekday mornings
- Shopping alias: hold everything until the weekend
Gatekeeper
Use gatekeeper when you need strict control over who can email an alias:
- A personal alias shared only with family
- A business alias used exclusively with one client
- A financial alias that should only receive from your bank
How Shield fits in the evaluation chain
Shield is evaluated after all other checks:
- IP blacklist check
- Spam scoring and threshold
- Contact rules (whitelist, block, mute)
- Filter rules
- Shield rules (rate limiter, snoozer, gatekeeper)
- Delivery to mailbox
This means a message must pass all prior checks before Shield is even considered. Shield adds the final layer of control before a message reaches your inbox.
Availability
Shield is available on all paid plans (Personal, Premium, Advanced, Enterprise). The free plan does not include Shield features.
There is no limit on how many aliases can have Shield enabled, or how many rules you can create per alias.
Enabling Shield on an alias
- Navigate to Aliases in the sidebar
- Click on the alias you want to protect
- Go to the Shield tab
- Enable the feature(s) you want: Rate Limiter, Snoozer, or Gatekeeper
- Configure the settings (see the dedicated guides for each feature)
- Save
Shield settings take effect immediately for all future messages to that alias.
