The short answer
At exactly 300 users you can still buy Microsoft 365 Copilot Business, which currently reads $18.00 per user per month paid yearly against a $21.00 list price, and Microsoft states it supports up to 300 users. The enterprise route, the Microsoft 365 Copilot add-on, is $30.00 per user per month and has no cap. For 300 seats that is $64,800 a year on Copilot Business against $108,000 on the add-on, a gap of $43,200. The catch is that the $18 is promotional and first year only, so the honest three-year comparison is against $21, and the moment you hire your 301st person the Business SKU stops being an option.
Last updated: August 2026. Prices read from the microsoft.com Microsoft 365 Copilot Business and Microsoft 365 Copilot pricing pages on August 24, 2026.
The 300-user line in Microsoft's Copilot pricing is the most consequential number in the whole licensing table, and it is almost never the number people ask about. Buyers ask what Copilot costs. The better question at this size is which Copilot you are still allowed to buy, because the answer changes by 67 percent per seat depending on which side of 300 you sit on, and it changes on a headcount you do not fully control.
This is written for the company sitting somewhere between roughly 200 and 400 people, on a Microsoft 365 Business plan, about to commit a year of budget. If you are already on E3 or E5 the decision is simpler and the numbers are on our Microsoft Copilot pricing page.
How much does Microsoft 365 Copilot cost for 300 users?
Two paths, two prices. Read from microsoft.com on August 24, 2026, both are per user per month on an annual commitment.
| Path | Per seat | 300 seats, one year | Cap |
|---|---|---|---|
| Copilot Business, promotional | $18.00 | $64,800 | Up to 300 users |
| Copilot Business, list | $21.00 | $75,600 | Up to 300 users |
| Microsoft 365 Copilot add-on | $30.00 | $108,000 | None |
Neither number is the whole bill. Both are add-ons. Microsoft is explicit that a qualifying base Microsoft 365 plan has to sit underneath, and for Copilot Business there is a second eligibility condition that most write-ups drop: the page states the add-on is "available only to existing Microsoft 365 customers with an eligible Business plan." It is not a way in for a company that has not already bought the base suite.
Is Copilot Business really limited to 300 users?
Yes. Microsoft's Copilot Business page states the SKU supports up to 300 users. It is a cliff, not a taper: there is no blended rate, no grandfathering language on the public page, and no partial tier. At 300 seats you pay $18 or $21. At 301 you are buying the $30 add-on, which is a 67 percent jump per seat off the promotional rate.
That cap sits on top of the base plan family, not beside it. Copilot Business attaches to Microsoft 365 Business plans, which carry their own 300-seat limit. So crossing 300 is usually two migrations at once, the base suite and the Copilot license, and the second is the one nobody budgets for.
What happens when we grow past 300 people?
You reprice. A 280-person company signing a one-year Copilot Business commitment today is not choosing $18 over $30, it is choosing when it starts paying $30. If your hiring plan says 340 people by next summer, model the enterprise number now, because the version of this decision that goes badly is the one where a finance team approved $64,800 and gets a renewal quote for $122,400 after a normal year of growth.
The pragmatic move at 250 to 300 seats is to run both numbers and ask the harder question underneath them: are you actually buying 300 seats, or are you buying 300 licenses and hoping for 120 users? Seat-level usage is the single biggest lever on this line item and almost nobody instruments it before the first renewal. If you already track how much of what you pay for actually gets used across your other tools, point the same discipline at this one, because a 40 percent activation rate turns a $30 seat into a $75 seat in practice.
Why is Copilot Business $18 and not $21?
It is a promotion, and the terms matter more than the number. Microsoft's page shows it as a strikethrough, "Originally starting from $21.00 now starting from $18.00 user/month, paid yearly," with a footnote that promotional pricing applies to the first year only. The offer window is stated as July 1, 2026 through December 31, 2026, and it "may not be combined with any other offer," which rules out stacking it on a partner or volume deal you already hold.
Sources disagree on the end date
This end date moved. When we read Microsoft's page on August 24, 2026 it stated July 1 to September 30, 2026, while widely-read licensing summaries said December 31. On a re-read of the same page on August 31, 2026 Microsoft states July 1 to December 31, 2026. We are recording both readings rather than quietly overwriting the first one, because it shows the window is something Microsoft edits. Whatever the page says on the day you sign, get the rate and the end date written onto the order form.
The $21 list price itself is recent. Secondary licensing sources report that Microsoft cut the small-business Copilot rate from $30 to $21 for organizations under 300 users in December 2025. Microsoft does not publish that history on the current page, so treat it as context rather than fact. What it tells you is that this SKU has repriced three times in under a year, which is a good reason to keep the renewal rate in writing rather than in a slide.
Which license should we buy at 300 users?
Buy Copilot Business if all three are true: you are on an eligible Microsoft 365 Business plan today, your realistic headcount stays under 300 for the length of the commitment, and your knowledge genuinely lives in Microsoft 365. In that shape it is the cheaper product for the same experience, and $43,200 a year is not a rounding error.
Buy the $30 add-on if you are within about 15 percent of the cap, if you are on E3 or E5 already, or if you want one license story that survives the next acquisition. Paying the higher rate to avoid a mid-term migration is a defensible trade at this size.
Buy neither, yet, if the problem you are trying to solve is that people cannot find things. That is a different purchase, and it is worth being precise about, because "our team wastes hours looking for answers" is the sentence that gets Copilot approved and it is the use case Copilot is weakest at outside Microsoft 365.
Does a Copilot license search Slack, Google Drive or Notion?
No. A Copilot license, at either price, reaches Microsoft 365 content. Reaching Slack, Google Drive, Notion, Confluence, Jira, Gmail or Salesforce means Microsoft Graph connectors or custom Copilot Studio agents, which is scoped engineering work with an owner and a maintenance cost, not a setting.
Agents also bill on a separate meter. Copilot Studio is sold tenant-wide in packs of 25,000 Copilot Credits at $200.00 per pack per month, and Microsoft Learn documents a pay-as-you-go option at $0.01 per message through an Azure subscription. Prepaid works out at $0.008 a message, so a pack is roughly 20 percent cheaper if you will use the capacity and 100 percent more expensive if you will not. Our breakdown of Copilot Studio versus Microsoft 365 Copilot licensing goes through the credit model in detail.
This is where the honest comparison sits for a 300-person company. If the answers you need are in SharePoint, Teams and Outlook, Copilot at $18 is good value and you should buy it. If half of them are in Slack threads and Drive folders, you are pricing a Copilot license plus connector engineering plus a credit meter against a dedicated unified search tool that covers those sources in the seat price. Run both totals rather than comparing $18 to a competitor's list price, because the $18 is not what you would end up spending.
The three-year view
Most companies at this size sign annually and think in one-year totals, which is exactly how the first-year-only condition catches people. Here is the same decision over three years for a company that starts at 280 seats and grows 10 percent a year, using Microsoft's published rates and no assumed discounts.
| Year | Seats | Rate available | Annual cost |
|---|---|---|---|
| Year 1 | 280 | $18.00 promotional | $60,480 |
| Year 2 | 308 | $30.00, over the cap | $110,880 |
| Year 3 | 339 | $30.00 | $122,040 |
Illustrative, using published rates only. The year-two jump is 83 percent, and it is caused by crossing 300 seats, not by a price increase.
That year-two number is the one to put in front of a CFO before signing year one. It is not a scare figure, it is arithmetic on Microsoft's own published rates, and a company that has seen it makes a much better decision about which SKU to start on.
Questions to ask your reseller before you sign
Five that change the total, in the order they usually get skipped.
- What is the rate at renewal, in writing on the order form, not the rate today?
- What happens on the day we exceed 300 seats: co-term, true-up, or a new agreement?
- Is the $18 promotional rate still available on our signature date, and under which offer terms?
- Which base plan does each user need underneath, and are all 300 already on an eligible one?
- If we need answers from non-Microsoft apps, what is the connector scope and who maintains it?
None of these are adversarial. A good reseller answers all five in one email, and the answers are what turn a $18-per-seat headline into a number you can defend.
Where this leaves you
At 300 users, Copilot Business is genuinely the cheaper license and Microsoft has priced it to be attractive to exactly your size of company. The two things to hold onto are that the $18 is a first-year promotional rate off a $21 list, and that the 300 cap is a cliff you can walk off by hiring normally. Model year two before you sign year one.
And separate the two purchases in your head. A Copilot license is a productivity add-on for Microsoft 365. Finding an answer that lives in a Slack thread, a Notion page and a Drive doc at the same time is a search problem, and it is worth pricing on its own terms. Our Microsoft Copilot alternatives page compares ten products on published price, reach and permissions, and permission-aware AI search covers the access-control test worth running before you shortlist anything.