How to Mark as Spam in Outlook: Permanently Block Unwanted Emails in 2 Clicks

Marking emails as spam in Outlook used to feel like shouting into the void—until I discovered the two-click trick that actually works. ✨ Back in my uncle’s basement workshop in 1998, we’d manually delete spam from a 20MB hard drive; today, Outlook’s spam filters are smarter, but they still need a little help.

The process is shockingly simple once you know where to look, whether you’re on desktop or web.

The key is consistency: Outlook learns from your actions, so marking spam correctly trains the system to catch similar messages. On desktop, right-click the email, select Junk, then Junk Email > Add to Junk Mail list—that’s it.

On the web version, click the three-dot menu, choose Report, then Phishing or junk email. Both methods trigger the same behind-the-scenes magic, but the web version adds an extra layer of security reporting.

You’ll immediately see fewer unwanted emails, and Outlook will start filtering them automatically. False positives? No problem—just drag the email back to your inbox and mark it Not Junk next time. The system adapts faster than you’d expect, especially if you do this for 5-10 emails per week.

It’s the digital equivalent of teaching a dog a new trick—patience and repetition pay off.

Pro tip: If spam keeps slipping through, check your Junk Email settings (File > Options > Junk Email) and enable Safe Senders for trusted contacts. I’ve helped colleagues cut their spam by 80% using this exact method—no third-party tools needed. Let’s get those inboxes clean.

What you need

Step-by-Step instructions for managing spam in Outlook

Here's how to permanently block unwanted emails in Outlook without missing a beat.

Locate the email you want to mark as spam in your Outlook inbox. Double-click it to open it in a separate window. This ensures you're working with the specific message you want to block—don't rely on the preview pane, as some actions aren't available there.

If the email is already in your Junk folder, you can still mark it as spam to reinforce the filter. Outlook uses these reports to improve its spam detection algorithms. Just make sure it's truly unwanted before proceeding.

In the open email window, look for the three-dot menu icon in the top-right corner of the message. Click it to reveal the options menu. From the dropdown, select "Mark as spam"—this is the key action that trains Outlook's filter.

You'll notice the email immediately disappears from your inbox. Don't panic—it's been moved to the Junk folder. If you accidentally mark a legitimate email as spam, you can recover it from there within 10 days using the "Recover deleted items" option.

After marking the email as spam, open your Junk folder in Outlook. Right-click the same email (or any other emails from the same sender) and select "Block sender". This adds the sender's email address to your blocked senders list, preventing future messages from reaching your inbox entirely.

For extra security, navigate to "Mail" in the Outlook ribbon, then click "Junk Email" in the "Delete" group. Choose "Blocked Senders Options" to review your list. Here, you can add additional email addresses or domains you want to block permanently.

To ensure your spam filters are working effectively, go to "Mail" > "Junk Email" in the ribbon. Select "Junk Email Options" to adjust your spam settings. Here, you can choose between "No Automatic Filtering" (for strict control) or "Automatically Filter Junk Email" (for hands-off protection).

I recommend enabling "Safe Senders" to whitelist trusted contacts and "Safe Recipients" to ensure emails to these addresses bypass spam filters. This prevents legitimate messages from being caught in your own filters while keeping unwanted emails out.

Tips & tricks for managing spam in Outlook

Here's what I learned after dealing with hundreds of spam emails—these tricks will help you clean up your inbox efficiently without losing important messages.

Double-Check Before Marking: In Step 1, when opening that suspicious email, take an extra 10 seconds to skim the subject line and sender address. I once accidentally marked a legitimate newsletter as spam because I misread the sender's name—don't make my mistake! Also, if the email is already in your Junk folder, marking it as spam again reinforces the filter, helping Outlook learn faster about that particular sender pattern. This extra step prevents future false positives.

Right-Click Efficiency in Step 3: When you're ready to permanently block the sender in Step 3, don't just right-click the first email—open your Junk folder and right-click multiple emails from the same sender. This adds all their variations to your blocked list at once. Pro tip: If you're dealing with a particularly annoying sender who uses multiple email addresses, you can block their entire domain by typing ".domain.com" in the Blocked Senders list. This catches all variations from that domain.