The First Map: Deciding Which Banks Qualify
Small-bank regulatory regimes need an eligibility boundary before they can offer a simpler capital, liquidity or reporting framework. The practical question is not merely how many assets a bank holds. It is whether the bank’s size, activities and condition make the proposed simplification a safe fit. This distinction helps readers judge an eligibility design by asking what each criterion captures, what it misses and which risk the tailored rule is allowed to leave out.
The Bank for International Settlements (BIS) comparison starts with three broad dimensions: size, complexity and risk profile. Authorities in different jurisdictions translate those dimensions into different thresholds and proxies. There is no globally portable definition of “small bank,” and the variation is not just a technical nuisance. It shows that eligibility is the first part of the mapping problem: the boundary has to be designed in relation to the banking system and the requirement that will be simplified.
Size is the starting signal, not the whole definition
Asset size is attractive as a regulatory screen because it is visible, measurable and relatively easy to administer. Across the six jurisdictions reviewed by the BIS, it is the only criterion they all share. Yet the reported thresholds vary widely, from about USD 1.44 billion to USD 27.2 billion. Brazil uses a threshold linked to gross domestic product rather than a permanently fixed dollar amount. The spread tells us that “small” is a relationship to a domestic banking system, not a universal number.
A fixed threshold offers certainty. A bank can usually tell whether its balance sheet is below the line, and supervisors can apply the rule without recalculating the boundary whenever the wider economy changes. The weakness is that a fixed number can age. Inflation, economic growth and changes in the size of the domestic banking sector can turn yesterday’s small-bank cutoff into a poor representation of today’s institutions. A threshold that once excluded systemically important firms may eventually admit them if the economy grows around it.
A dynamic threshold addresses some of that problem. Linking the boundary to GDP or another changing measure can keep eligibility closer to the scale of the domestic economy. It also adds administrative complexity and may make planning less predictable. The trade-off is not between a correct and an incorrect threshold. It is between a simpler rule that can become stale and a more responsive rule that is harder to administer and forecast.
Time-averaged thresholds offer another response to volatility. Instead of allowing a bank’s status to change because of one temporary balance-sheet movement, an authority can look at assets over several preceding years. This gives a growing bank time to prepare for leaving the simplified regime and reduces the incentive to manage a single reporting date. But smoothing is not the same as ignoring growth. A bank that persistently expands still needs a route out of the regime.
Size also has a boundary that is easy to overlook: an institution can be small today and capable of becoming significant tomorrow. The BIS cautions that a threshold should not make an institution eligible when it could become systemic “in life or in death”—that is, through its growth or through the consequences of its failure. Size is therefore a useful first filter, but a threshold alone cannot distinguish a straightforward local lender from a small institution whose activities or connections create risks out of proportion to its assets.
Complexity proxies identify what size cannot see
Complexity is not an abstract label for “difficult banks.” It is a set of observable activities and structures that make a simplified rule less informative or less safe. The BIS comparison identifies several types of proxy: limits on trading-book exposures, restrictions on derivatives and commodities, prohibitions or limits on internal ratings-based models, domestic-activity conditions and caps on off-balance-sheet exposures.
A trading-book limit is a direct example. If a simplified capital regime does not measure market risk with the same detail as a full framework, limiting the bank’s trading activity narrows the risk that the simplified measure fails to capture. The eligibility condition is not an unrelated obstacle. It is the boundary that makes the simplification intelligible.
Derivatives and commodities can create similar problems. Their exposures may depend on counterparty behavior, changing market values and legal or operational arrangements that are not visible from a simple total-assets figure. A small bank that does not hold meaningful positions in these activities may not need every calculation designed for them. A bank that does hold them may no longer fit the assumptions behind the simpler regime, even if its balance sheet remains below the size threshold.
Internal ratings-based models raise a different kind of complexity. They rely on institution-specific methods for estimating credit risk rather than applying only a standardized approach. The issue is not that internal models are inherently unsafe. It is that a regime designed for a simple, standardized bank may not be the right home for an institution whose risk measurement depends on more elaborate models, validation and supervisory review.
Off-balance-sheet exposures show why denominators and boundaries matter. A bank’s total assets do not reveal every commitment, guarantee or other exposure that may create risk. The U.S. small-bank leverage approach, for example, uses a leverage calculation that excludes off-balance-sheet exposures, while the Swiss small-bank approach includes them. The difference does not by itself establish that one method is better. It shows why an eligibility design may need a separate limit on off-balance-sheet activity when the simplified measure does not include it.
The underlying principle is conditional: the more risk a simplified calculation leaves unmeasured, the more important it is to restrict the activities that generate that risk. A complexity proxy should therefore be judged by the requirement it supports. A trading limit may be relevant to a capital simplification but not sufficient to decide whether a bank should receive reduced market disclosure. A restriction on cross-border business may matter to a domestic small-bank regime but say little about the quality of its liquidity management.
Domestic scope is part of the business model
A regime intended for small, locally focused banks may use geographic conditions to prevent a bank from qualifying while operating mainly through international connections. In the BIS comparison, China bars cross-border exposures for banks under its small-bank regime. The European Union and United Kingdom use domestic-activity requirements that require a substantial share of assets, liabilities or credit exposures to remain within their relevant domestic area.
These conditions do more than draw a line on a map. They preserve the relationship between the bank’s business model and the rationale for proportional treatment. A local lender is often evaluated on the basis that its structure, customers and risks are relatively understandable within the domestic supervisory system. As cross-border activity grows, the bank may face different legal environments, counterparties, funding channels and resolution questions. The operational complexity can grow before the asset-size threshold does.
Domestic-activity rules also expose a tension in the word “local.” A bank can have a small balance sheet but still be connected to a wider group or rely on external activities that change its risk. Eligibility may therefore require more than counting the bank’s own assets. The BIS reports that the United Kingdom considers the size and activities of a wider group for some eligibility questions rather than treating every subsidiary as automatically independent.
A geographic proxy is not a claim that cross-border activity is always dangerous or that local activity is always safe. It is a way to align the scope of the bank with the supervisory and prudential assumptions behind a tailored regime. Like a trading cap, it should be connected to the risks the authority is choosing to measure less intensively.
Risk profile completes the screen
A bank can be small and operationally simple but still not be in a condition to receive regulatory relief. Risk-profile criteria address that problem. The BIS groups them into supervisory assessments and financial resilience measures. Supervisors may consider the institution’s overall condition, management or governance quality, formal supervisory actions and related indicators. Authorities may also require minimum leverage or liquidity measures.
Supervisory assessment is useful because not every relevant fact appears in a size or activity statistic. A bank may have a simple balance sheet but weak governance, unresolved supervisory concerns or risk-management problems. A condition-based filter can keep such an institution from receiving a simplification whose safety depends on competent management. It also creates an incentive-compatible boundary: the benefit is available to small banks that remain in satisfactory condition, rather than to every institution that crosses an asset threshold.
That approach has limits. Supervisory judgment is not a mechanical measurement, and the BIS does not evaluate how consistently the sampled jurisdictions apply it. A condition rating can change, and a formal measure may lag behind a new risk. For that reason, financial metrics can provide an additional floor. A minimum leverage ratio or liquidity requirement does not describe the entire risk profile, but it can demonstrate that an eligible bank has a basic resilience buffer.
Financial metrics also need to match the simplification. If the proposed relief replaces a risk-based capital framework with a leverage ratio, a leverage condition may be central to eligibility. If the proposal exempts a bank from a quantitative liquidity standard, a liquidity measure or a funding condition may be more relevant. One metric cannot stand in for every risk. The filter should be chosen for the rule that is changing.
The resulting screen is multidimensional:
The arrows should not be read as a universal legal sequence. Some jurisdictions use automatic classification based on size; others offer an opt-in regime subject to multiple conditions. The diagram expresses the design logic: each screen removes a different source of mismatch between a simplified rule and the bank that would use it.
Why the criterion must match the simplification
The strongest eligibility designs start with the requirement that will change and work backward. Suppose an authority wants to remove detailed market-risk capital calculations. It should ask which banks have small enough trading exposures that the omission is tolerable, then cap or prohibit activities that would make the omission material. If the authority wants to replace risk-based capital with a leverage measure, it should examine the denominator, off-balance-sheet exposures and the level of leverage required. If it wants to reduce reporting, it should identify which information supervisors still need to see.
This approach prevents two opposite errors. The first is over-inclusion: a bank qualifies because it is small even though it conducts activities that the simplified rule does not capture. The second is over-exclusion: an authority applies a broad set of conditions that add nearly as much complexity as the framework it was meant to simplify. A proxy is worthwhile when it removes a meaningful mismatch at a lower cost than the requirement it supports.
It is also why no single jurisdiction’s eligibility formula can simply be transplanted. The BIS comparison is descriptive, not a finding that one threshold or proxy is optimal. Domestic banking structures differ, and so do the legal powers, supervisory practices and risks that authorities are trying to manage. A useful comparison asks what each criterion is doing, not which country has the shortest list.
The conclusion is that size identifies a candidate population, while complexity and risk profile decide whether a particular bank fits a particular simplification. That fit is not permanent. Banks grow, change activities and move in or out of financial condition. A defensible regime must therefore answer a further question: how should eligibility behave when the bank temporarily crosses a boundary, and when should it leave the simpler framework altogether?