What is the Copilot Credits Pre-Purchase Plan?
The Pre-Purchase Plan (Microsoft calls it P3) lets a business buy a year's worth of Copilot Credits upfront at a discount, instead of paying $0.01 each as you go. There are nine tiers, from 5% off at 300,000 credits to 20% off at 300 million. Anything you use beyond your tier is billed at pay-as-you-go, and unused credits expire at the end of the one-year term.
From Microsoft's Copilot Credits Guide (September 2026). Upfront cost in pounds at this site's cautious £1 = $1.27, ex-VAT. Break-even is the monthly usage at which the plan stops costing you more than pay-as-you-go would have.
| Tier | Credits a year | Discount | Upfront (£) | Break-even a month |
|---|---|---|---|---|
| 1 | 300,000 | 5% | £2,244 | 23,750 credits |
| 2 | 1,500,000 | 6% | £11,102 | 117,500 credits |
| 3 | 3,000,000 | 7% | £21,969 | 232,500 credits |
| 4 | 15,000,000 | 8% | £108,661 | 1,150,000 credits |
| 5 | 30,000,000 | 10% | £212,598 | 2,250,000 credits |
| 6 | 75,000,000 | 12% | £519,685 | 5,500,000 credits |
| 7 | 150,000,000 | 14% | £1,015,748 | 10,750,000 credits |
| 8 | 225,000,000 | 17% | £1,470,472 | 15,562,500 credits |
| 9 | 300,000,000 | 20% | £1,889,764 | 20,000,000 credits |
Usage beyond your tier is billed at pay-as-you-go. Unused credits expire at the end of the one-year term.
The useful way to read that table is backwards. Don't ask which tier your usage fits; ask which tier you are certain to use in full. A firm spending about 200,000 credits a month uses 2.4 million a year, so the sensible commitment is tier 2 - 1.5 million credits at 6% off - with everything above it on pay-as-you-go. That saves roughly £700 a year at this site's rate, carries no expiry risk, and the busy months still work.
Buying the tier that matches your forecast exactly is the tempting mistake. Forecasts for a tool a few months old are optimistic, usage dips in August and at Christmas, and every credit you don't use is money gone. Committing to the floor - the volume your quietest realistic year would still reach - gets most of the discount with none of that risk.
Keep it in proportion, too. The discount is on usage only; the Copilot licence and the Microsoft 365 plan under it don't move. For most smaller businesses, licences are a bigger lever than a 5% or 6% usage discount - deciding which desks earn a licence will usually save more than any pre-purchase. And give it six months of real usage data first: P3 is a decision for steady usage, not a launch-day choice.
Tier 1 is 300,000 credits at 5% off: $2,850 upfront, about £2,244 at this site's cautious £1 = $1.27 (ex-VAT). It only beats pay-as-you-go if you'd use at least 285,000 credits over the year - about 23,750 a month.
Usage beyond the pre-purchased credits continues at the pay-as-you-go rate. Running over is not a problem - it's the intended pattern if you commit to the floor. Running under is the expensive mistake, because unused credits expire.
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