Copilot Cowork: Decoding the Real Cost of Each Model
Since the general availability launch of Copilot Cowork in June 2026, choosing an AI model directly impacts your billing. Unlike the information displayed in the selector, pricing gaps between models can reach 270%. This article helps you understand the actual pricing structure and make informed budgetary decisions.
Key Point
Each Copilot Cowork model consumes a different amount of credits for an identical task. The selector labels describe capabilities, not costs.
How Copilot Cowork Models Work and Billing
Credit-Based Pricing Structure
The Copilot Cowork billing model is based on credit consumption, charged at €0.01 per credit in pay-as-you-go mode. Four main elements influence the total cost of a task:
- The choice of model (an element you control directly)
- Context retrieval
- Tool calls
- Execution time
The model selector remains one of the most important levers for controlling your spending, particularly because it depends entirely on your choices.
Four Available Options
Microsoft offers four models in the Copilot Cowork selector:
- Auto: Automatic orchestration adapted to the task (default)
- Claude Sonnet 4.6: Labeled as "efficient for daily tasks"
- Claude Opus 4.8: Positioned for "complex and critical work"
- GPT 5.5: Presented as "versatile for all types of tasks"
Microsoft's official documentation recommends keeping Auto mode for most routine operations. However, this recommendation masks a more nuanced pricing reality.
Comparative Test: Analysis of Real Costs by Model
Test Results on an Identical Task
I executed an identical Cowork task on three different models, with the same deliverables requested. The task included:
- Processing a CSV file containing 2025 business data
- Generating a multi-sheet Excel workbook
- Creating a PowerPoint presentation ready for an executive committee
- Developing an interactive HTML dashboard
After each execution, I used the /cost command to verify exact consumption.
| Model | Credits Consumed | Cost (Pay-as-You-Go) |
|---|---|---|
| Claude Sonnet 4.6 | 398 | €3.98 |
| Claude Opus 4.8 | 477 | €4.77 |
| GPT 5.5 | 1,069 | €10.69 |
Interpretation of Results
GPT 5.5 consumes 2.7 times more credits than Sonnet for identical results. Opus positions itself as an intermediate alternative, with an overhead of approximately €0.80 for in-depth reasoning capability.
The pricing gap does not reflect a difference in deliverable quality. By maintaining a constant output UI through a custom Skill, the consumption gap comes exclusively from the model itself.
Beware of Marketing Positioning
The label "versatile for all types of tasks" (GPT 5.5) is misleading. Its cost is equivalent to running Sonnet and Opus combined for the same task.
Decoding Selector Labels and Budget Implications
The Gap Between Promise and Pricing Reality
The labels offered by Microsoft ("efficient", "complex and critical", "versatile") function as a behavioral design surface. They describe appropriate use cases, not pricing structure.
An IT administrator or rational user faced with three options would naturally tend to choose the "versatile" option as a safe compromise. Yet, this choice multiplies the cost by 2 to 3 for tasks that Sonnet would handle without any quality difference.
Impact on Monthly Budgets
This type of pricing trap affects teams that don't actively test their models. Over one month:
- 100 tasks via Sonnet: ~€398
- 100 tasks via GPT 5.5: ~€1,069
- Monthly overage: ~€671
Microsoft's official Copilot Credits guide does not break down consumption by model, leaving the selector to do most of the user guidance work.
Selecting the Right Model by Task Type
Selection Best Practices
Use Sonnet 4.6 for Routine Tasks
Sonnet is suitable for routine work: writing, summarization, data restructuring, standard artifact generation. Its positioning as "efficient for daily tasks" corresponds to 80% of operational needs. The cost per task remains in the low to mid-range bracket.
Reserve Opus 4.8 for Complex Tasks
Use Opus only for work justifying multi-source analysis, nuanced research synthesis, or decisions where a reasoning error would have significant cost. The credit gap between Sonnet and Opus (around 80 cents) remains acceptable for these use cases. Always test before setting it as default: the additional quality is often marginal.
Configure Auto for Mixed Workloads
The Auto mode automatically orchestrates by task and tends to favor less expensive models. Position it as the default for mixed workflows, particularly when coupled with a custom Skill that stabilizes the output format.
Reserve GPT 5.5 for Specialized Cases
GPT 5.5 addresses specific needs: long-form writing, citation-heavy outputs, large context windows. Treat it as a specialized model, never as a general default.
Budget Control Tip
After each model test, execute the /cost command to get exact consumption. This exercise takes one minute and quickly builds your pricing intuition before monthly billing.
Mastering Copilot Cowork Costs: Synthetic Recommendations
Pricing Strategy by Usage Profile
For cost-focused teams: Set Sonnet 4.6 as the default model. The cost is predictable and the quality sufficient for the majority of use cases.
For mixed operations: Keep Auto enabled. Automatic orchestration reduces manual decisions while avoiding overages.
For data science or research teams: Create a usage policy that reserves GPT 5.5 for truly justified cases, with prior ROI validation.
Continuous Monitoring and Optimization
The recommended methodology:
- Test each task type on at least two different models
- Compare results via
/costto understand the real gap - Document your model choices by task category
- Audit monthly actual vs budgeted consumption
The model selector remains your primary budget control lever. Each click directly changes what your invoice shows at month's end.
Frequently Asked Questions About Copilot Cowork
What models are available in Copilot Cowork?
Copilot Cowork offers four models in the selector: Auto (default orchestrator), Claude Sonnet 4.6 (daily tasks), Claude Opus 4.8 (complex work), and GPT 5.5 (versatile). Some tenants also offer a coupled mode Sonnet + Opus Advisor. Available options depend on your organization's policies.
What is the exact cost of each Copilot Cowork model?
There is no fixed price per task. Billing works in Copilot Credits (€0.01 per credit). On my identical-task test: Sonnet 4.6 = 398 credits (€3.98), Opus 4.8 = 477 credits (€4.77), GPT 5.5 = 1,069 credits (€10.69). Prompt complexity, context retrieval, tool calls, and execution duration all influence the final total.
Which model should I use by default?
Choose Auto if you don't want to manage this selection. Sonnet 4.6 is the safe default for predictable, stable cost. Use Opus 4.8 for nuanced reasoning or critical decisions. GPT 5.5 addresses exclusively long-form writing or heavily cited outputs. See the previous section for detailed use case guidance.
How do I know the exact cost of a Cowork task?
Type /cost in the task window after execution. Cowork returns the exact number of Copilot Credits consumed to that point. Use this command after each model test to compare fairly. It's the most direct way to anticipate your invoice before month's end.
Critical Budget Management Point
The lack of model pricing detail in Microsoft documentation creates a classic trap: without active testing, teams drift toward GPT 5.5 (positioned as "versatile") and see their bills explode without understanding why.
Conclusion: The Credits Model as a Management Discipline
The Copilot Credits meter imposes a new IT management discipline. Model selection is the primary adjustment lever. The selector labels describe capabilities, not pricing structure.
The most effective practice remains simple: execute the same task on two different models, compare via /cost, and document your recommendations. Over a monthly cycle, these small decisions compound into significant budgetary gaps.
