BUSINESSNew tool · · 2 min read · Source: Microsoft Learn
Microsoft Copilot: New top models run on separate credits
Microsoft is adding the GPT-6 Astra and Claude Fable 5.1 models to the Copilot model selector. According to a Microsoft notice, the worldwide rollout starts in early November 2026 and should finish by mid-November, with usage paid for in Copilot Credits.
Key facts
- GPT-6 Astra and Claude Fable 5.1 reach the model selector worldwide from early November 2026, according to Microsoft, finishing by mid-November.
- Available in Copilot chat and in Word, Excel and PowerPoint; requires a Copilot license, enabled billing and allocated credits.
- Auto, GPT 5.6 and Sonnet remain included in the license (fair use), and Opus with limits.
What's changing
Both models can be selected in chat in the Copilot app and in Copilot for Word, Excel and PowerPoint. They aren't simply switched on for everyone, though. Notice MC1519122 lists three requirements:
- a Microsoft 365 Copilot license,
- usage-based billing enabled for that person,
- credits allocated to them.
Without that setup, employees can't use these models, so they won't land on the bill by accident.
What stays in the license
Microsoft splits work into two tiers. The fixed license covers everyday tasks such as summaries, drafts and analysis. That includes Auto, the default mode, which picks a model for each request. GPT 5.6 and Sonnet are included under fair use, and Opus with limits. Credits apply to advanced work such as Cowork, Code and the newest frontier models. Microsoft also says that soon, anyone who reaches a license limit can continue on credits or, where applicable, switch back to Auto.
How companies control the cost
Admins set up spending policies in the Microsoft 365 admin center. They can decide who gets access, set limits per policy and per person, and configure alerts. Depending on the service, billing can run through a pre-purchase plan, pay-as-you-go or prepaid capacity. One setting deserves a look: "Auto-apply new services" is on by default, so existing policies automatically extend to future services unless admins turn it off. Microsoft advises reviewing expected credit use before allocating credits. The notice doesn't give a price per request.
What this means for you
- The top models in Word and Excel aren't a free upgrade to the Copilot license. They are an extra, usage-based cost.
- For everyday work, Microsoft points to Auto. The expensive models make more sense for clearly defined, demanding tasks.
- If you enable billing, set a budget, limits and a rule for who may request more credits first.
How to use this
If your company uses Microsoft 365 Copilot, review the spending policies in the admin center with IT before anyone gets credits. Start with a small pilot group and a fixed monthly limit.
Luigi's take
This shows where AI software is heading: away from flat fees and toward a base license plus usage. That makes sense, since long-running tasks cost vendors a lot of compute. For marketing and finance leaders, though, AI is becoming a budget line that can swing like ad spend. It should be run like one, with a monthly budget, an owner and regular reviews.
My advice: don't enable this for everyone just because the newest model is tempting. Pick two or three people with clear tasks, set a tight limit and, after four weeks, compare the results with what Auto delivers. If the difference isn't noticeable, stick with the license. The best model is the one whose extra cost you can justify to your boss in a single sentence.
Source
Microsoft Learn: Understanding the user subscription license (USL) and usage-based billing (UBB)
More sources
- Microsoft Learn – Abrechnungswege und Ausgabenregeln
- Message Center Archive – Wortlaut der Microsoft-Mitteilung MC1519122 vom 21.10.2026
This article was researched and written with AI assistance. Responsible: Luigi Lugmayr.
