Microsoft SNDS: The Complete Guide to Outlook.com IP Reputation Data (2026)

Microsoft SNDS (Smart Network Data Services) is Microsoft's free portal that shows IP owners how Outlook.com sees their mail: daily volume, the share flagged as spam (green, yellow or red), complaint rate, and whether an IP is blocked. It also runs JMRP, the feedback loop that reports which Outlook.com users marked your mail as junk. Microsoft's current SNDS portal is https://substrate.office.com/ip-domain-management-snds/snds. Microsoft says it replaces the previous site and that network access expires 10 months after approval or migration.

This guide covers what SNDS shows and how to read it, how to set it up, what it cannot tell you, how JMRP works, and which Microsoft support path to use when an IP is blocked. Use it alongside Microsoft's current sender guidance.

What SNDS is (and is not)

Microsoft describes SNDS as a way for senders responsible for IP space to see data from Outlook.com's inbound mail systems. It covers Microsoft's consumer services, including outlook.com, hotmail.com, live.com and msn.com addresses.

What SNDS is not:

• Not a Microsoft 365 tool. It says nothing about how business tenants on Microsoft 365 filter your mail.
• Not domain reputation. Everything is keyed to IP addresses.
• Not a repair button. Microsoft's own welcome text: "just looking at the data isn't enough... Reputation is always the responsibility of the sender."

A useful way to think about it: SNDS is the smoke detector for your IPs at Microsoft. It tells you something is burning, roughly how badly, and when it started. It does not tell you which room, and it will not put the fire out.

What SNDS shows: the View Data columns

For each authorized IP, SNDS reports daily activity and reputation signals. The current portal is the source of truth for the fields and definitions shown to your account.

Filter result colors

Microsoft defines the color by the percentage of recipients that received a spam verdict. One message to ten recipients counts as ten verdicts.

Two cautions from Microsoft. The color is a filter verdict, not an inbox rate, because user safe lists and settings can rescue or harden placement afterward. And mismatches between color, complaint rate and block status are "not indicative of a bug." Filtered mail gets fewer complaints because users never see it, so a red IP can show a low complaint rate.

Reference points to validate in the current portal

• Complaint rate: use the complaint-rate trend as a list-quality signal. Do not turn one day into a universal threshold; compare it with volume, filter result and the affected stream.
• Failed recipients: compare RCPT commands with message recipients. A widening gap can point to stale addresses or address-harvesting behavior, but confirm the cause in bounce logs and sending-system data.

IP Status page

The View IP Status page lists IPs with an abnormal status, current as of the last 24 hours with no history:

Data timing and retention

Microsoft aggregates data by IP and day. Low-volume or inactive IPs may show little or no useful data, so an empty view is not proof that a sending system is healthy. Confirm the actual sending IP and the account's current authorization before troubleshooting further.

How to set up SNDS (new portal)

1. Sign in at https://substrate.office.com/ip-domain-management-snds/snds with a Microsoft account.
2. Request access to the IPs for which you are responsible. Microsoft presents an authorization flow for those networks.
3. Complete the ownership check using the contact method shown for the network, then return to SNDS after the authorization is accepted.
4. Enroll in JMRP for the same authorized IPs if you need complaint reports.
5. Record the approval date and owner. Microsoft says access expires 10 months after approval or migration, and the current portal warns that the first reattestation reminder can show an inaccurate deadline.

Things that go wrong:

• No authorization addresses returned. Request a smaller range, or fix your rDNS or registry contacts. Microsoft says the SNDS team "cannot manually adjust authorizations" and will not process manual access requests.
• You cannot receive mail at the offered addresses. Have whoever can (often your hosting provider) complete the authorization and delegate: they forward you the link or click it on your behalf.
• Access disappears months later. Network access now expires 10 months after approval or migration. Microsoft sends three reminder emails; the first shipped with a wrong deadline date, which Microsoft acknowledged on September 22, 2026. Put reattestation on a shared calendar, not one person's inbox.

What current primary sources confirm

Microsoft's current primary-source announcement confirms three operational facts:

Microsoft's public Services page says JMRP is a free service that returns the full message with headers for junk or phishing reports and typically starts feedback within as little as 72 hours. Treat vendor-reported dates, undocumented API behavior, trap-count retirement, and header-only formats as unverified unless a current Microsoft source or your account receipt confirms them.

JMRP: the Junk Mail Reporting Program

JMRP is Microsoft's feedback loop. When an Outlook.com user clicks Report junk on your message, Microsoft sends an ARF report to the address you configured. Microsoft says feedback typically starts "within as little as 72 hours" of enrollment.

How to use it well:

• Suppress every complainer immediately. That is the whole point. A complainer who keeps receiving mail keeps complaining.
• Make complaints traceable. Put a campaign or stream identifier in your message headers so you can map a complaint back to the sending system. Confirm the fields your current JMRP report returns before depending on a specific header format.
• Use a durable mailbox. Point feeds at a role address, not an employee.
• Update JMRP when IPs change. Microsoft's troubleshooting page reminds senders to add new IPs to JMRP.
• Read the SNDS comments column. "JMR Block" shows when an IP is blocked due to complaints, and on shared IPs you see all complaints regardless of which domain sent the mail.

The limits of SNDS

SNDS is valuable if you own dedicated IPs with real volume. For many B2B senders it shows little or nothing.

If SNDS cannot see your mail, use placement tests on Outlook.com and Microsoft 365 mailboxes, header analysis (see the Outlook spam filter guide), bounce codes and blocklist checks.

SNDS vs Google Postmaster Tools

For the Google-side comparison, consult the current Google Postmaster Tools guide when that route is live.

Reading SNDS alongside Postmaster Tools and your own data

A practical weekly routine for dedicated-IP senders:

1. Line up the dates. SNDS activity periods use the Pacific-time day, while Google Postmaster Tools uses UTC and your ESP may use either. Align before comparing.
2. Compare direction, not absolute numbers. If Gmail spam rate rises and SNDS complaints rise in the same week, investigate list quality, content, volume and provider-specific filtering together.
3. Split by provider. If Gmail is clean and SNDS is yellow, look at what is different about Microsoft recipients: B2B-heavy segments, older addresses, or a campaign that went mostly to Hotmail.
4. Check the RCPT to recipients gap. A rising gap means bad addresses are creeping in before bounces show it in your ESP.
5. Log changes. Any IP, DNS, volume or template change goes in a changelog so an SNDS shift can be traced to a cause.

Getting delisted: which Microsoft channel to use

SNDS is a monitoring service, not the delisting form. Start with Microsoft's current Postmaster Troubleshooting and sender-support path, then use the channel that matches the bounce:

What to include in an Outlook.com sender support request: the sending IPs, sending domain, the full bounce text, UTC timestamps of first and latest occurrence, sample recipient domains, and what you changed. State whether you are enrolled in SNDS and JMRP.

What to expect:

• Provide evidence. Include the IP, full bounce, timestamps, sending domain and the corrective action taken.
• Allow processing time. Microsoft says Microsoft 365 delisting might take up to 24 hours or longer.
• Fix the cause first. If the cause is not fixed, an IP can be blocked again.

For any third-party blocklist, follow that list's current removal instructions separately from Microsoft's sender-support process.

When SNDS is not worth your time

• Your Outlook.com volume is too low to produce useful SNDS signals.
• You send only from Google Workspace or Microsoft 365 mailboxes.
• Your ESP runs you on a shared pool and does not share SNDS data.
• Your audience is almost entirely B2B on Microsoft 365, where SNDS has no visibility.

In those cases, spend the time on placement testing, authentication and list hygiene instead.

How Folderly fills the gaps SNDS leaves

SNDS gives dedicated-IP senders Microsoft's view of their IPs. Most B2B outbound teams do not have that view at all, because they send from Workspace or Microsoft 365 mailboxes. Use the live Folderly domain reputation checker and DMARC checker for separate domain-level and authentication checks when SNDS cannot see the sending IP.

FAQ

What is Microsoft SNDS?

Microsoft Smart Network Data Services (SNDS) is a free Outlook.com portal that shows IP owners how Microsoft's consumer mail system sees traffic from their IPs: daily volume, the share flagged as spam (green, yellow or red), complaint rate, and whether an IP is blocked, junked or flagged as a bot. It also hosts the Junk Mail Reporting Program, which reports when Outlook.com users mark your mail as junk.

What is the new SNDS URL?

Microsoft's current SNDS portal is https://substrate.office.com/ip-domain-management-snds/snds. Microsoft says it replaces the previous site. Update bookmarks and follow the current authorization instructions; the portal announcement also says network access expires 10 months after approval or migration and that the first reattestation reminder can show an inaccurate deadline.

Why does SNDS show no data for my IP?

The current portal warns that low-volume or inactive IPs may show little or no useful data. Confirm the actual sending IP and current authorization before troubleshooting; Microsoft aggregates SNDS data by IP and day.

What do the SNDS colors mean?

The filter result color is the share of recipients for which Microsoft's spam filter returned a spam verdict that day. Green means under 10%, yellow means 10% to 90%, and red means over 90%. One message to ten recipients counts as ten verdicts. It is not an inbox placement rate, because user safe lists and settings can move messages after filtering.

Can I use SNDS with Google Workspace, Microsoft 365 or a shared ESP IP?

Not directly. SNDS authorizes you by proving control of the IP range through reverse DNS or registry contacts, so you only see IPs you own or that your provider delegates to you. Mail from Google Workspace or Microsoft 365 mailboxes leaves from Google's or Microsoft's IPs. On a shared ESP pool, only the ESP can register, and the data mixes every customer on those IPs.

What is JMRP and how do I sign up?

The Junk Mail Reporting Program is Microsoft's feedback loop for Outlook.com. Microsoft's current Services page says JMRP returns the full message with headers for mail reported as junk or phishing and typically starts feedback within as little as 72 hours. Enroll from JMRP in SNDS for IPs you are authorized to manage.

How do I get my IP unblocked by Outlook.com?

Fix the cause first, then start at Microsoft's current Postmaster Troubleshooting page and use its sender-support path for the relevant Outlook.com block. Include the IP, full bounce text and timestamps. Microsoft 365 blocks use different routes: sender.office.com for 5.7.606 to 5.7.649 bounces, or delist@microsoft.com for 5.7.511.

Is SNDS the same as Google Postmaster Tools?

No. Google Postmaster Tools is domain-based: you verify a domain and see spam rate, compliance status and delivery errors for mail to Gmail. SNDS is IP-based: you prove ownership of IPs and see filter verdicts and complaints for mail to Outlook.com. Microsoft offers no domain-level equivalent for external senders, so senders on shared infrastructure rely on seed testing and complaint data instead.

Last reviewed: September 28, 2026.