If this week’s Microsoft 365 outage affected your organisation, Microsoft may owe you money back. Under its service level agreement (SLA), Microsoft promises that Microsoft 365 will be available 99.9% of the time each month, and this outage went well past that. Below, we explain what happened, what you could claim, and how we’ll make the claim for you.
From about 16:17 GMT on Thursday 12 November 2026, many people couldn’t get into their Microsoft 365 email. At midday on Friday 13 November, nearly 20 hours later, Microsoft was still restoring service.
Microsoft says a process on its email servers that sets up secure connections became overloaded, and the remaining servers couldn’t keep up. It has confirmed this was not a cyberattack. In your Microsoft 365 admin center, the outage appears as incidents EX1550543 and MO1550821.
Services affected:
Across the UK, schools, hospitals, police forces and Parliament reported disruption. Downdetector logged more than 7,600 Outlook problem reports from UK users on Friday morning.
Microsoft is restoring service region by region. It has extended how long it holds undelivered email to 48 hours, so delayed messages should still arrive, though they may come in batches.
When Microsoft misses its 99.9% monthly uptime target, you can claim a service credit: a discount on what you pay for the affected service. The lower the uptime, the bigger the credit.
Microsoft 365 SLA
When Microsoft misses its 99.9% monthly uptime target, you can claim a discount on the affected service. The lower the uptime, the bigger the credit.
| Monthly uptime below | Service credit | Downtime in November |
|---|---|---|
| 99.9% | 25% | About 43 minutes |
| 99% | 50%Possible band | About 7.2 hours |
| 95% | 100% | 36 hours |
Based on a 30-day month. Microsoft works out the final credit for each organisation from how many users were affected and for how long.
Get in TouchIf your team couldn’t use email for most of this outage, you could fall into the 50% band, or higher if the outage passes 36 hours. Microsoft works out the final figure from how many of your users were affected and for how long.
Before you claim, it helps to know:
If we manage your Microsoft 365 licences, we are already preparing your claim. All we need from you is one email.
Please reply by Friday 27 November, so we can get every claim in well before Microsoft’s 31 December deadline. Microsoft makes the final decision on each claim and on how much it credits, and we’ll keep you updated along the way.
Who makes the claim depends on where you bought your licences.
Not sure where your licences came from? Check Billing > Your products in the admin center.
What Microsoft will ask for:
If you bought through a partner, the claim must reach Microsoft by 31 December 2026, so it’s worth starting now.
No cloud service is perfect. This outage shows why every organisation should have a business continuity plan (BCP): an agreed, written plan for keeping essential work going when something goes wrong. Despite the name, it isn’t only for businesses: schools, trusts and charities need one just as much. An IT continuity plan is the part of it that covers your systems, data and communication. You can then act quickly and calmly instead of improvising.
For the IT side of your plan, decide:
A plan only works if people know it, so review it at least once a year and test it with a short practice run. If you don’t have one yet, we can help you put one together.
We are based in Tewkesbury and support schools and multi-academy trusts, charities and small and medium businesses with proactive IT support, cyber-security and strategic consultancy. That includes keeping an eye on Microsoft 365 service health, so we spot problems early and claim SLA credits for you when Microsoft falls short. We also write IT continuity plans for all kinds of organisations, not just businesses, then help test them and keep them up to date, so your team knows exactly what to do when the next outage comes.
Want help with a claim, or with writing and testing your IT continuity plan? Get in touch and let’s book a meeting.
Microsoft 365 outage
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Under its service level agreement (SLA), Microsoft promises that Microsoft 365 will be available 99.9% of the time each month. When it misses that target, you can claim a service credit: a percentage off what you pay for the affected service.
Credits are 25% if uptime falls below 99.9%, 50% below 99%, and 100% below 95%. If your team couldn't use email for most of this outage, you could fall into the 50% band.
Microsoft decides the final figure for each organisation, based on how many users were affected and for how long.
No. It's a credit that comes off a future bill. It only covers the service that was affected, such as Exchange Online, not your whole Microsoft 365 plan.
For licences bought through a Cloud Solution Provider (CSP) partner, Microsoft must receive the claim within one month of the end of the billing month the outage happened in. For this outage, that's 31 December 2026.
If you're a Spectrum IT client, please reply to our email by Friday 27 November so we have time to submit every claim.
Just reply to our email from your work email address. Confirm that you were affected, roughly how many people it affected, and that you'd like us to claim on your behalf. We'll gather the evidence, submit the claim and pass any approved credit on to you on a future invoice.
Microsoft only accepts confirmation sent from the email domain of the affected Microsoft 365 account. It rejects requests sent from personal addresses, such as Gmail or Hotmail.
If you bought your licences through an IT partner, ask them to claim for you. If you bought directly from Microsoft, raise a support request in the Microsoft 365 admin center under Support > Help & support, and quote incidents EX1550543 and MO1550821.
Either way, you'll need your tenant ID, the times you were affected, the number of users affected, and a written request from your work email address.
No. Service credits only apply to paid subscriptions.
Microsoft has said the outage was not caused by malicious activity. However, scammers often take advantage of outages. Be wary of unexpected calls or messages offering to "fix" your account, or asking you to re-verify your password. Report anything suspicious to your IT team.
An IT continuity plan is the part of your business continuity plan (BCP) that covers systems, data and communication. It sets out how you'll stay in touch, how you'll reach your data in a longer outage, and who does what.
Every organisation should have one, including schools, trusts and charities. Spectrum IT can write your plan, help you test it and keep it up to date.
Let’s discuss how we can best assist your organisation with its IT & digital challenges. No matter how big or small, our team of experts will work with you to determine the best actions forward for your IT.