Exchange Anti-Spam Filtering: Setting Up Recipient Filters

If you want to add multiple specific email addresses to Exchange’s Anti-Spam Recipient Filtering block list, you can do this in one command via Exchange Management Shell rather than adding them one at a time.

The Command

Set-RecipientFilterConfig -BlockedRecipients [email protected],[email protected],[email protected]

Add as many comma-separated addresses as you need in the list.

Important: This Replaces, Not Appends

Set-RecipientFilterConfig -BlockedRecipients replaces the entire blocked list with whatever you specify, rather than adding to the existing one. If you already have blocked recipients configured and want to add more without losing them, pull the current list first, merge it with your additions, and pass the full combined list back in — or check the current list with Get-RecipientFilterConfig | Select BlockedRecipients before making changes so you know what you’d be overwriting. Also confirm Recipient Filtering itself is enabled on your Receive Connector/Anti-Spam agents — on Exchange installations where the anti-spam agents aren’t installed by default (common on Mailbox role servers without the Edge Transport role), this cmdlet configures the setting but it won’t have any effect until the anti-spam agents are enabled.

Still Current on Exchange Server SE (Updated for 2026)

Set-RecipientFilterConfig -BlockedRecipients remains unchanged on the current on-premises Exchange release, Exchange Server Subscription Edition (Exchange Server SE, which reached general availability on 1 July 2025 and continues receiving cumulative updates) — this cmdlet is on-premises only, with a maximum of 800 blocked SMTP addresses per list. Worth double-checking the script name if you’re setting this up from scratch on a Mailbox-role-only server: the anti-spam agents this post relies on (Content Filter, Sender Filter, Sender ID, Protocol Analysis, and the Recipient Filter agent) aren’t installed by default, and the install script is Install-AntispamAgents.ps1. If you’re managing Exchange Online instead of an on-premises server, none of this applies — there’s no cloud equivalent of Set-RecipientFilterConfig; blocked senders/recipients and spam thresholds for Exchange Online mailboxes are configured through anti-spam policies in the Microsoft Defender portal instead.

Resources

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