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How to Block Emails in Outlook
Blocking a sender takes ten seconds. Blocking your way to a quiet inbox does not work, and here is the arithmetic on why.
Try it with your OutlookOutlook's way: the blocked senders list
- 1New Outlook and Outlook on the web: Settings → Mail → Junk email. Add an address under Blocked senders, or a whole domain under Blocked domains, then Save.
- 2Classic Outlook desktop: right-click the message → Block → Block Sender. Or Home tab → Delete group → Block → Junk E-mail Options → Blocked Senders → Add.
- 3Blocking a domain rather than an address catches every sender behind it, which is the efficient move when one company mails you from six addresses.
- 4To unblock, return to the same list and remove the entry.
The problem
- ✕Blocked mail lands in Junk Email, and Microsoft deletes anything there after 14 days with no recovery — so a wrongly blocked sender is gone before you notice
- ✕The blocked senders and safe senders lists hold up to 10,000 entries, which sounds generous until you are adding one per cold email
- ✕New Outlook does not offer blocking for third-party accounts such as Gmail or Yahoo connected into it; those are configured at the provider
- ✕Blocking is retrospective. Every new sender gets one free run at your inbox before you can block them.
- ✕Most inbox noise is not from senders you would block — it is real mail that simply is not urgent
What Clarity does: sort the mail you are not going to block
- 1Keep using Outlook's blocked senders list for genuine abuse — Clarity does not block, unsubscribe, or delete anything.
- 2Clarity reads what arrives and decides what it actually is: a question waiting on you, a thread waiting on someone else, or something informational.
- 3It applies a native Outlook category, so newsletters and notifications are visibly marked rather than mixed in with client mail.
- 4Your morning brief covers what needs you. Marketing and notifications are categorised but kept out of it.
What changes
- ✓No list to maintain and no 10,000-entry ceiling
- ✓Nothing is deleted or diverted to Junk, so nothing disappears after 14 days
- ✓A first-time sender is judged on what they wrote, not on whether they are already on a list
- ✓Works server-side, so categories are there before you open the app
Who runs into this
Business owner
Blocks a recruiter a week and the volume never drops, because it is a new firm every time.
Operations lead
Blocked a supplier's mailing list and lost the delivery notifications that came from the same domain.
Founder
The problem is not spam. It is two hundred legitimate emails and no way to see the four that matter.
Frequently asked questions
How do I block an email address in Outlook?
In new Outlook or on the web, go to Settings → Mail → Junk email and add the address under Blocked senders, then Save. In classic Outlook, right-click the message and choose Block → Block Sender.
Can I block an entire domain in Outlook?
Yes. In new Outlook and on the web there is a separate Blocked domains list under Settings → Mail → Junk email. Microsoft recommends blocking domains rather than individual addresses when you are close to the list limit.
How many senders can I block in Outlook?
Microsoft states the blocked senders and safe senders lists hold up to 10,000 addresses or domains between them.
Where do blocked emails go?
To the Junk Email folder. Microsoft deletes messages there automatically after 14 days, and they cannot be recovered afterwards, so check the folder before that window closes if you have blocked something by mistake.
Does Clarity block or unsubscribe from emails?
No. Clarity does not block senders, unsubscribe on your behalf, or delete mail. It categorises what arrives so newsletters and notifications are marked and stay out of your morning brief.
Looking for Microsoft's own documentation? Microsoft's blocked senders documentation
More Outlook guides
Auto-Categorise Emails with AI
Stop building rules by hand. Clarity reads every email and applies the right Outlook category.
How to Organise Your Outlook Inbox
Folders, categories, rules and Focused Inbox — what each is for and why they decay.
Daily Email Summary
A morning brief of what needs your attention — prioritized by urgency, noise filtered out.
What it costs you
Roughly 9.1 hours a week
Estimate2.8 hrs of that we could cover
The rest stays yours — it is not repeatable.
106 hrs
a year, if the low end of the range holds
137
threads went quiet and nothing told you
Last 90 days · your own mail · illustrative figures
Clarity Inbox
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