Teams using GitHub Copilot need to separate three dates instead of treating “the September changes” as a single event. On September 1, 2026, GitHub starts reopening self-service sign-ups for Copilot Business and Copilot Enterprise customers paying by credit card or PayPal, with updated billing behavior for new seat assignments. On September 28, two changes may begin — but the announcement says no earlier than September 28, so rollout may happen that day or later: the unification of Copilot Chat on github.com, GitHub Mobile, and Copilot cloud agent under one policy, and the change that makes the code review “Default” effort map from Lite to Balanced. For existing Business and Enterprise customers paying by credit card or PayPal, the billing updates take effect starting October 1, 2026.
The practical task is to review configuration, governance, and budget before September 28 without assuming changes are already active. The official August 28 announcement is in the GitHub Changelog.
What is already in effect on September 1 — and what is not
On September 1, the immediate milestone is the gradual reopening of self-service sign-ups for new Business and Enterprise customers paying by credit card or PayPal. GitHub says new Business or Enterprise seat assignments will require payment before the user gets Copilot access. The company is also strengthening account vetting and updating the billing experience for these payment methods.
This does not mean the Balanced code review default or the new chat-retention behavior is already in effect on September 1. Those two items are tied to the relaunch scheduled for no earlier than September 28, 2026. Likewise, existing Business and Enterprise customers paying by credit card or PayPal should look to October 1 as the start of the billing updates for their existing subscriptions.
Decision matrix: change, affected teams, where to review, and required decision
| Change | Who is affected | Where to review | Decision required |
|---|---|---|---|
| Seat payment and updated billing | New self-service Business/Enterprise customers and, starting October 1, eligible existing customers paying by credit card or PayPal | Billing, seats, budgets, and usage | Confirm necessary seats, budget for additional usage, and billing cycle |
| Unified policy for Copilot on github.com, Mobile, and cloud agent | Business/Enterprise organizations that manage access through policy | Copilot settings; Copilot cloud agent option when available | Decide whether the unified experience should remain enabled for teams |
| Chat retention on github.com changes from 28 days to account lifetime | Users and organizations using Copilot on github.com after migration | Internal AI-use policies, data classification, and governance | Reassess what can be sent to chat and whether the longer retention fits internal rules |
| Code review “Default” changes from Lite to Balanced | Organizations and repositories using the Default value | Organization/Repository Settings > Copilot > Code review | Keep Default and accept Balanced, or explicitly pin Lite before the change |
Billing: what changes and what belongs on the checklist
The September announcement is not a price increase for Copilot Business or Enterprise. GitHub says the prices of those plans are not changing. What changes is the billing and access behavior.
- New seats: new Business or Enterprise seat assignments require payment before the user gets access.
- Upfront cycle charge: at the start of the next billing cycle, all assigned seats will incur an upfront charge. For existing customers paying by credit card or PayPal, this update starts October 1, 2026.
- Usage beyond included amounts: additional payment may be required for users to continue using Copilot after included usage is exceeded.
- Proration: included usage may be prorated through the month to align with seat-cost proration.
- Seat removal: revoking a seat does not produce a prorated refund; the removal is reflected in the next monthly billing cycle.
- Existing controls: spend controls, usage tracking, and the ability to buy additional AI Credits remain available.
For finance or platform teams, the most useful action is to compare assigned seats, actually active users, budgets, and additional consumption before the next cycle. GitHub has already used usage-based billing for Copilot since June 2026; that context is in the billing and plans changelog. The September update mainly changes how and when seats and usage need to be covered by payment.
Retention: why the unified policy deserves a governance review
In the relaunch scheduled for no earlier than September 28, Copilot Chat on github.com, Copilot Chat in GitHub Mobile, and Copilot cloud agent will share a single experience and policy. That unified experience will be enabled by default after launch.
The most sensitive governance change is on github.com: as the service moves to the agent sessions experience, chat data will be retained for the life of the account instead of 28 days, aligning with the existing Copilot cloud agent behavior.
The announcement says no action is required to keep Copilot available on github.com and GitHub Mobile. However, if the organization opts out of the unified experience, it will lose access to Copilot on those two channels after the new model launches. GitHub therefore advises Business and Enterprise administrators to review the policy before September 28.
Operational implication: longer retention changes the automatic-deletion assumption some teams may have used when deciding what was acceptable to send to chat. It is worth reviewing internal rules for secrets, personal data, confidential code, and customer information. That is an organization-specific governance decision; GitHub announces the retention change but does not replace each company's internal policy.
Code review: “Default” will stop meaning Lite
GitHub Copilot code review currently supports effort levels. Lite prioritizes faster, targeted review, while Balanced uses deeper analysis for complex logic, security-sensitive code, and cross-service changes. GitHub's documentation says Balanced uses more AI Credits and may consume marginally more GitHub Actions minutes than Lite.
The migration point is precise: starting September 28, for organizations and repositories configured as Default, that value will use Balanced. If a team wants to preserve Lite, simply “leaving things as they are” is not enough: it must change Default to Lite explicitly at the organization or repository level before the date.
The hierarchy matters as well. The organization default applies to repositories that have not selected their own level; the repository default applies to automatically requested reviews in that repository. For manually requested reviews, the effort level can be chosen from the pull request's reviewers menu. See the code review configuration documentation.
There is a potential cost impact. The current code review documentation estimates roughly US$0.05 to US$1 in AI Credits for a Lite review and US$0.25 to US$5 for a Balanced review, excluding Actions minutes. GitHub notes that consumption varies with pull request size, repository instructions, and model evolution. For teams with automatic review across many PRs, silently moving from Default/Lite to Balanced can increase consumption even if pull request volume does not change.
Checklist to complete before September 28
- Map ownership by layer: identify who owns billing, Copilot policies, organization settings, and repository overrides.
- Inventory seats: identify assigned seats with little or no real usage and account for the fact that seat revocation does not create a prorated refund.
- Review budgets and consumption: check AI Credits, additional usage, and GitHub Actions for teams using code review.
- Decide on the unified policy: confirm whether Copilot on github.com and Mobile should remain enabled after the relaunch.
- Update the retention assessment: treat “account lifetime” as the new reference for github.com chats after migration, not 28 days.
- List repositories using Default: identify where code review inherits the organization setting and where local overrides exist.
- Choose Lite or Balanced intentionally: if you want Lite, configure it explicitly before September 28; if you accept Balanced, adjust cost and review-depth expectations.
- Record the decision: document the owner, selected configuration, and review date to avoid invisible changes between organization and repository levels.
What does not need to be treated as a September 1 emergency
There is no need to pull the retention or Balanced-default change forward to September 1: GitHub marked those items for no earlier than September 28. There is also no announced increase in the nominal price of Copilot Business or Enterprise. September's work is mainly about making decisions before defaults and policies change, not rushing to reconfigure everything on the first day of the month.
In short: on September 1, focus on sign-ups and new seat assignments; before September 28, finalize the decision on unified policy, retention, and code review effort; and if your organization is an existing Business or Enterprise customer paying by credit card or PayPal, prepare billing for the changes that begin October 1.
