How to Block Spam Emails on Gmail, Outlook, and Apple Mail

Every email client has tools to block spam. Most people never use them — or use them wrong. Here's exactly how to block unwanted email on the three most popular platforms, step by step, plus the one strategy that works better than all of them combined.

Gmail

Gmail's spam filter is already one of the best in the industry, catching over 99.9% of spam automatically. But plenty still slips through, especially marketing emails from companies you once interacted with. Here's how to take control.

Block a Specific Sender

1. Open the unwanted email.
2. Click the three dots (more options) next to the reply button in the top right.
3. Select "Block [sender name]."
4. Confirm by clicking Block in the popup.

All future messages from that sender go straight to spam. You can unblock later from Settings > See all settings > Filters and Blocked Addresses.

Filter by Sender Domain

Blocking one address doesn't help when a company sends from multiple addresses at the same domain. To block everything from a domain:

1. Click the search bar at the top of Gmail.
2. Click the filter icon (Show search options) on the right side of the search bar.
3. In the "From" field, type @spammydomain.com.
4. Click "Create filter."
5. Check "Delete it" (or "Skip Inbox" and "Apply label" if you want to review later).
6. Optionally check "Also apply filter to matching conversations" to clean up existing messages.
7. Click "Create filter."

Mark as Spam

Select the message and click "Report spam" (the exclamation mark icon). This moves the message to spam and trains Gmail's filter to catch similar messages in the future. Do this consistently — it's the most effective way to improve Gmail's accuracy for your account specifically.

Use Gmail's Built-In Unsubscribe

Gmail detects unsubscribe links in marketing emails and surfaces them as a button next to the sender's name. This is safer than scrolling to the bottom of the email because Gmail processes the unsubscribe on your behalf without requiring you to visit the sender's website.

The "+" Addressing Trick

Gmail ignores everything between a + and the @ in your address. So you+shopping@gmail.com delivers to the same inbox as you@gmail.com. Use this to create service-specific variants:

• you+amazon@gmail.com for Amazon
• you+newsletter@gmail.com for newsletters
• you+trial@gmail.com for free trials

You can then create filters based on the "to" address to automatically label, archive, or delete messages. The limitation: some signup forms reject addresses with +, and sophisticated spammers strip the + portion to find your real address.

Outlook

Outlook (both the web app and desktop client) offers several blocking tools that go beyond simple sender blocking.

Block a Sender

1. Right-click the unwanted message.
2. Select "Block" (web) or "Junk > Block Sender" (desktop).
3. Future messages from that address go to the Junk Email folder.

Block an Entire Domain

1. Go to Settings (gear icon) > Mail > Junk email.
2. Under "Blocked senders and domains," click "+ Add."
3. Enter the domain (e.g., spammycompany.com) and click Save.

All email from any address at that domain gets blocked. This is more effective than blocking individual senders, since companies often send from multiple addresses.

Use the Sweep Rule

Sweep is one of Outlook's most useful and least-known features:

1. Right-click a message from a sender you want to clean up.
2. Select "Sweep."
3. Choose one of four options:
   • Delete all messages from this sender — removes every existing message.
   • Delete all and block future messages — cleans up and blocks.
   • Keep only the latest message — useful for daily digests.
   • Always delete messages older than 10 days — keeps your inbox tidy automatically.

Manage Your Safe Senders List

If Outlook's filter is too aggressive and catching legitimate mail, add trusted senders to the Safe Senders list:

1. Go to Settings > Mail > Junk email.
2. Under "Safe senders and domains," click "+ Add."
3. Enter the address or domain.

Messages from safe senders always reach your inbox, regardless of content.

Apple Mail

Apple Mail's spam handling is simpler than Gmail's or Outlook's, but it covers the basics well — and the macOS version offers powerful rule-based filtering.

Block a Sender on macOS

1. Open the unwanted message.
2. Click the sender's name in the header.
3. In the dropdown, click "Block Contact."

Blocked messages get moved to Trash automatically. You can manage your blocked list from Mail > Settings > Junk Mail.

Block a Sender on iOS / iPadOS

1. Open the unwanted message.
2. Tap the sender's name at the top.
3. Tap the name again in the expanded header.
4. Scroll down and tap "Block this Contact."

The behavior matches macOS: future messages from that sender go to Trash.

Train the Junk Mail Filter

Apple Mail has a built-in Bayesian filter that learns from your behavior:

1. Select an unwanted message.
2. Click the "Move to Junk" button in the toolbar (or right-click and select "Move to Junk").
3. For messages incorrectly flagged as junk, select them in the Junk folder and click "Not Junk."

The filter improves over time. The more consistently you use it, the more accurate it becomes.

Create Mail Rules (macOS)

For advanced control, macOS Mail lets you create custom rules:

1. Go to Mail > Settings > Rules.
2. Click "Add Rule."
3. Set conditions like "From contains @spammydomain.com" or "Subject contains [specific keyword]."
4. Set the action: "Delete Message," "Move to Junk," or "Move to Mailbox."
5. Click OK and apply to existing messages if prompted.

Rules run automatically on incoming mail. You can create multiple rules and they execute in order — useful for building a comprehensive filtering system.

General Tips That Work Everywhere

Platform-specific tools help, but these habits work regardless of which email client you use.

Don't open suspected spam. Many spam emails contain tracking pixels — invisible images that notify the sender when the message is opened. This confirms your address is active. If you can tell it's spam from the subject line, delete it without opening.

Never click unsubscribe in obvious spam. Legitimate marketing emails from companies you recognize? Unsubscribe. Random emails from senders you've never heard of? Don't click anything. The "unsubscribe" link in a spam email often leads to a phishing page or simply confirms your address is active.

The real fix: stop giving your real email out. Blocking and filtering are reactive. They deal with spam after it arrives. The proactive solution is to prevent spam at the source by using disposable email addresses for signups that don't need your real address.

With a service like Reusable.Email, you can create a throwaway address in seconds — no signup needed. Use it for free trials, account creation, and one-time signups. The spam goes to an inbox you never check, and your real inbox stays clean.

For the full strategy — including long-term prevention and compartmentalization — see How to Stop Spam Email: The Complete 2026 Guide.

Blocking spam is necessary. Preventing it is better.