Microsoft's Outlook Outage Could Earn Businesses a 50% Credit — But Only If They Claim It

By Amara Osei

Businesses hit by this week's global Microsoft 365 outage can claim service credits worth up to 50 percent of their monthly fees — but Microsoft won't pay automatically, and claims for the November 2026 incident must land by the end of December 2026.

The outage began Thursday afternoon and left millions of Outlook users locked out of their mailboxes. It also disrupted other Microsoft 365 services, including Teams. Some customers reported issues lasting more than 18 hours while engineers worked to restore access.

"We are deeply sorry for the disruption this incident has caused our customers and partners," Microsoft said in a statement on X. "We know the trust they place in our services and take that responsibility extremely seriously."

Microsoft attributed the failure to a technical issue stemming from an earlier network-capacity upgrade that surfaced following a recent network change. The company said the outage was not a cyberattack and had no connection to AI agents.

"We have addressed the underlying issue and continue to restore service to remaining customers and regions," Microsoft said. "Given the scale of demand, we restored services gradually, validating stability at each stage. While this took longer, it helped ensure a stable restoration."

How much could your business get?

Microsoft's service-level agreements set three credit tiers. Customers qualify for a 25 percent credit if monthly uptime falls below 99.9 percent, a 50 percent credit if it drops below 99 percent, and a 100 percent credit if it falls below 95 percent.

Tony Redmond, a Microsoft Most Valuable Professional and independent Microsoft 365 consultant, ran the numbers. A hypothetical 15-hour outage affecting all users on a business's Microsoft 365 account would push Exchange Online's monthly uptime to roughly 97.9 percent — enough to trigger the 50 percent tier.

That doesn't guarantee half the monthly fees back, though. The payout depends on the subscription agreement, the length of the disruption, and how many users were affected.

"Microsoft calculates availability using affected user-minutes, not simply elapsed incident time," Redmond told Inc. "Given the catastrophic nature of the November 2026 outage, it's fair to assume that every user was affected. I don't see how individual users remained unaffected."

That formula produces uneven outcomes. A company where only half its employees lost access for 15 hours could receive a smaller credit than one where every employee went down for the same stretch. Microsoft hasn't released an official outage duration, so any credit calculation remains preliminary.

The credit also doesn't cover a full Microsoft 365 subscription. Microsoft calculates it on fees tied to the specific affected service, such as Exchange Online.

What won't Microsoft cover?

Businesses that lost real money shouldn't expect reimbursement. Under Microsoft's service agreements, credits are the customer's sole contractual remedy for qualifying disruptions. They don't cover lost revenue, operational costs, or other indirect losses.

How do you file a claim?

Customers must submit a claim documenting how the outage disrupted their services. Microsoft's Partner Center guidance says businesses may need to provide identifying information for the affected account plus evidence showing how the incident affected operations.

Redmond said claims for the November outage must be submitted by the end of December 2026. Companies buying Microsoft 365 directly from Microsoft can file through its support channels. Those purchasing through a Cloud Solution Provider should contact that provider.

"Start talking to whoever they purchase the Microsoft 365 service from about what's happening and how best to proceed," Redmond said. "Document everything!"

Microsoft plans to publish a full post-incident report after completing its review. That report could clarify the outage's true duration and impact — and sharpen the credit math.

For businesses aiming to avoid a repeat, Redmond recommended keeping an emergency communication channel, such as email accounts with another provider.

"Having an emergency ability to function is always a good thing," Redmond said. "But replacing a highly integrated, highly functional system like Microsoft 365 is very difficult, especially with the amount of data now stored in the cloud."

Microsoft did not immediately respond to a request for comment.