The Federal Reserve Finalized Its Stress Test Overhaul on September 30. Here's What Your Capital Planning Team Needs to Know Before December 1.

TL;DR

• The Federal Reserve finalized two stress test rules on September 30, 2026, effective approximately December 1; the September 19 regulatory preview was written before the rules were final
• Jump-off date moves from December 31 to September 30; stress capital buffer effective date shifts from October 1 to January 1 — changing both the starting balance sheet and the capital planning calendar
• Two-year averaging of the stress capital buffer begins with the 2028 test — not 2027 — and is designed to halve year-over-year volatility without changing aggregate capital levels
• Model transparency is a substantive change: beginning with the 2027 test, the Fed publishes equations, variables, and coefficients for each supervisory model by August 31 of the prior year
• PPNR models were not finalized — they were re-proposed and require a separate tracking process

On September 18, 2026, this site published a preview of the Federal Reserve’s expected stress test overhaul. The FAQ for that post stated, explicitly: “Has the Federal Reserve finalized the stress test overhaul? Not as of September 18, 2026.”

Twelve days later, on September 30, the Fed finalized two rules that implement the changes Vice Chair for Supervision Michelle Bowman had previewed. The final rules are largely consistent with the proposal — with one significant exception that has direct capital planning consequences.

This post covers what actually changed, what the calendar implications are, and what capital planning teams need to do before the rules take effect.

The Two Rules the Fed Actually Finalized

The Fed issued two separate final rules on September 30, 2026, published in the Federal Register on October 2.

Rule One: Enhanced Transparency and Public Accountability. This rule establishes the model disclosure framework, restructures the scenario design process, and changes the stress test calendar. It is the more operationally consequential of the two for risk and capital teams.

Rule Two: Modifications to the Capital Plan Rule and Stress Capital Buffer Requirement. This rule implements two-year averaging for the stress capital buffer calculation beginning with the 2028 test and codifies related changes to the capital planning framework.

One item from the September preview was not finalized: the pre-provision net revenue (PPNR) models. The Fed received public feedback that the PPNR model changes were material enough to require another comment period. A separate re-proposal for PPNR is pending.

What the Transparency Rule Actually Does

Model Documentation Published Before Each Test

Beginning with the 2027 supervisory stress test, the Fed will publish detailed technical documentation for each supervisory model. The documentation includes:

• Model equations, variables, and coefficients
• Underlying assumptions and limitations
• Decision-making rationale
• Alternative model approaches the Fed considered
• Planned changes for the upcoming test year

For banks that have been modeling the supervisory stress test internally, this is a significant information upgrade. The prior practice — running internal scenarios while guessing at model specifications — is replaced by a transparent baseline. Banks with sophisticated pre-testing capabilities can now calibrate against the Fed’s actual models.

The disclosure deadline is August 31 of the year before the test. For the 2027 test, the Fed will publish this documentation by August 31, 2026. Wait — that date has already passed, which means the 2027 test transparency documentation should already be available. Capital planning teams should verify whether the Fed has published 2027 model documentation consistent with the rule.

Annual Public Comment on Scenarios and Material Changes

The Fed will now invite public comment annually on the stress test scenarios and any material model changes. Material model changes must be proposed by August 31 of the prior year, with a comment period of at least 30 days.

This gives trade groups and banks a formal channel to flag concerns about scenario design before the test runs. From a compliance standpoint, it also means there is now a public record of what the Fed considered when designing scenarios — useful context if an institution disputes a stress test outcome.

Two Global Market Shocks for Trading Book Firms

Banks with large trading books (Category I and II firms subject to the global market shock component) will now be tested against two separate global market shock scenarios each year. The Fed uses the shock that produces the larger losses for each firm in calculating stress capital buffer requirements.

This change does not affect institutions below the trading book threshold, but for the largest banks it means internal market risk models need to stress against two distinct scenarios rather than one.

Calendar Changes

Two calendar changes affect internal planning processes:

Jump-off date. The stress test now starts from September 30 balance sheet data rather than December 31. For a 2027 test, this means the starting balance sheet reflects September 30, 2026 — data that capital planning teams should already be treating as a planning input.

SCB effective date. Moving the stress capital buffer effective date from October 1 to January 1 aligns the capital requirement with the calendar year. Banks now have an additional three months before a new SCB requirement takes effect. This is a meaningful planning buffer: Q4 capital actions that would have raced against an October 1 deadline now have until January 1.

What Two-Year Averaging Actually Means

The most structurally significant change is two-year averaging of stress capital buffer requirements, beginning with the 2028 test.

Under the prior framework, each year’s SCB requirement was set entirely by that year’s stress test results. A bad year — driven by a more severe scenario, model changes, or balance sheet composition shifts — could produce a large SCB increase with a one-year lag. The Fed’s own analysis showed year-over-year SCB volatility was a recurring source of uncertainty in capital planning.

Under two-year averaging, the SCB requirement will reflect the average of a firm’s two most recent annual stress test results. The Fed estimates this approach reduces year-over-year volatility in capital requirements by approximately 50 percent.

What this does not do: It does not reduce aggregate capital requirements. The Fed’s modeling indicates the averaging approach preserves overall capital levels while smoothing the volatility. Institutions should not model this as capital relief.

Timing: The averaging begins with the 2028 stress test. The 2027 test will still produce an SCB based on the single 2027 result. Capital plans for the 2027 cycle should not assume averaging.

Transition mechanics: Banks subject to the stress test in both of the two averaging years use the average. Banks subject in only one year use the single-year result. The practical implication: a firm entering or exiting the $100 billion asset threshold during the averaging window needs to model the asymmetric treatment.

What PPNR Re-Proposal Means for Capital Teams

PPNR — pre-provision net revenue — is the model that projects a bank’s core income over the stress horizon. It directly affects the net loss figure in stress test results, and model design choices have historically been a major source of unexplained volatility between a bank’s internal PPNR projection and the Fed’s supervisory projection.

The Fed received public comments indicating its proposed PPNR changes were substantive enough to require a second comment period. The re-proposed rule is now a separate regulatory process.

Capital planning teams should:

1. Track the PPNR re-proposal independently — it is not covered by the December 1 effective date of the two finalized rules
2. Avoid assuming the PPNR changes are final; model your 2027 stress test against current specifications until the re-proposal resolves
3. Review public comments on the PPNR re-proposal when filed — they often surface model design concerns that affect your internal projection assumptions

What Capital Planning Teams Need to Do Before December 1

The rules are effective approximately December 1, 2026. Here is the immediate action list for capital planning and risk management teams:

1. Update your stress test calendar. The jump-off date change affects which balance sheet data feeds your internal stress test preparation. September 30, 2026 is the baseline for the 2027 test. Confirm your internal capital planning process is using September 30 data as the starting point, not December 31.

2. Adjust SCB buffer planning timelines. The SCB effective date shifts from October 1 to January 1. If your capital distribution planning (dividends, buybacks) assumed an October 1 reset, update the timeline. You have until January 1, 2027 before a new SCB applies from the 2027 test.

3. Verify whether 2027 model documentation is available. The rule requires the Fed to publish 2027 model specifications by August 31, 2026. Confirm whether the Fed has published this documentation — if it has, your internal stress testing team should be validating against it now.

4. Do not model 2027 with averaging. Two-year averaging begins with the 2028 test. Your 2027 capital plan should use the single-year 2027 result.

5. Begin tracking the PPNR re-proposal. PPNR is the most direct driver of differences between internal and supervisory stress test results for income-intensive institutions. The re-proposal is a separate process with its own comment period — monitor it.

6. Review the two-shock trading book requirement. If your institution is subject to the global market shock, your market risk team needs to run two scenario variants for the 2027 test and use the worse outcome.

Why This Matters Beyond Capital Requirements

The model transparency component has implications beyond capital planning mechanics. For the first time, banks subject to the supervisory stress test will have access to the Fed’s actual model specifications before the test runs. This changes the dynamic of the internal-versus-supervisory divergence conversation.

Historically, when a bank’s internally projected capital position diverged significantly from the Fed’s supervisory projection, the conversation was constrained by limited visibility into the Fed’s models. With equation-level disclosure, capital planning teams can now identify where their projections diverge from the supervisory model’s assumptions and articulate that clearly to senior management and the board.

This is useful for two reasons. First, it improves the quality of internal capital plans — plans calibrated against the actual supervisory model rather than a best guess. Second, it makes the capital adequacy discussion with the board more defensible. When a director asks why the supervisory projection differs from management’s projection, the answer can now cite specific modeling assumptions rather than “we don’t know how the Fed models this.”

The Basel III endgame capital re-proposal from March 2026 adds further context here. Capital planning for large institutions is navigating simultaneous changes to the stress test framework and the risk-weighted asset calculation. Teams tracking both developments need to model the interaction effects — a stress capital buffer calibrated against September 30 data under the new model transparency framework, on top of an RWA denominator that may change when Basel III endgame finalizes.

For the full list of Q4 2026 compliance deadlines affecting capital and risk programs, see the Q4 2026 compliance action calendar.

So What?

The Federal Reserve’s September 30 final rules land in a capital planning environment already stressed by Basel III endgame, the OCC/FDIC unsafe or unsound practice redefinition, and the November 2, 2026 effective dates for multiple other regulatory changes.

The stress test changes are not an immediate capital crisis. Two-year averaging does not take effect until 2028. The SCB effective date shifts actually extend your planning window by three months.

What is immediate: the calendar and data changes. September 30 is now your planning baseline. If your 2027 internal capital plan was built on December 31, 2026 data, it needs to be rebuilt from September 30 data. That is a real operational change, and it needs to be complete before the rules take effect in December.

The model transparency provision is the longer-term benefit. For the first time, capital planning professionals will have equation-level insight into the supervisory models driving their capital requirements. Institutions that build internal modeling infrastructure to use that transparency will produce more credible capital plans and have more defensible conversations with supervisors. Those that treat the rule change as administrative and continue manual divergence analysis will fall behind.

The Enterprise Risk Management Framework includes capital adequacy planning templates, stress testing scenario documentation, and board-level capital reporting structures. See it here.

Sources:

• Federal Reserve Board: Federal Reserve Board finalizes changes to enhance the transparency and public accountability of its stress test
• Federal Register: Modifications to the Capital Plan Rule and Stress Capital Buffer Requirement
• Federal Reserve: Final Rule Text — Enhanced Transparency and Modifications to the Capital Plan Rule
• ABA Banking Journal: Fed finalizes new stress test rules