What it means
Not all capital is equally useful in a crisis. CET1 counts only the funding that can absorb losses while a bank continues trading, which means ordinary shares, share premium, retained earnings and certain reserves, rather than debt-like instruments that must eventually be repaid.
The concept matters beyond banking, because a bank's CET1 position determines how much it can lend, whether it can pay dividends and how confidently it will price a facility. A business owner negotiating a loan is, indirectly, negotiating against the bank's capital constraints.
Calculating CET1 starts with the accounting equity on the balance sheet and then removes items regulators do not trust to absorb losses. Goodwill and other intangible assets are deducted because they evaporate in a stress event, and certain deferred tax assets are deducted because they are only worth something if the bank returns to profit.
The framework was tightened substantially after the 2008 financial crisis, when it became clear that some banks reported healthy-looking capital that turned out to be of poor quality. The response was to define a narrow, strict measure of loss-absorbing equity and require far more of it.
CET1 is the numerator in the widely quoted CET1 ratio, and it also sits at the top of a stack that includes Additional Tier 1 and Tier 2 capital. Those lower tiers can absorb losses too, but only later or under specific conditions, which is why analysts and regulators watch CET1 most closely.
Building CET1 is slow work, which is the point. A bank grows it mainly by retaining profits rather than paying them out, or by issuing new ordinary shares, and both routes have a visible cost to existing shareholders, so capital decisions and dividend policy end up being the same conversation.
In practice
Real-world examples.
Example
A bank plans a $400 million share buyback, then models the effect on CET1 and finds the resulting position uncomfortably close to its internal floor. The buyback is halved and the remainder deferred to the following year.
Example
An acquisitive bank buys a smaller competitor and books $180 million of goodwill. Because goodwill is deducted in full, the deal consumes CET1 immediately even though accounting equity appears unchanged.
Example
A corporate treasurer comparing two lenders reviews each bank's published CET1 figure alongside its ratio and its trend over the past eight quarters. The better capitalised lender is chosen for a five-year facility, on the reasoning that a bank with more loss-absorbing equity is less likely to withdraw credit part way through a downturn.
Think of it
“CET1 is your strongest capital-the core equity that absorbs losses first.
Formula
Calculation
CET1 capital = Ordinary shares and share premium + Retained earnings + Accumulated other comprehensive income and qualifying reserves - Regulatory deductions. A mid-sized bank reports ordinary shares and share premium of $1,200 million, retained earnings of $900 million and other comprehensive income of $50 million, giving a subtotal of $2,150 million. Regulatory deductions are goodwill of $180 million, other intangible assets of $70 million and deferred tax assets that rely on future profits of $50 million, a total of $300 million. CET1 capital is therefore $2,150 million - $300 million = $1,850 million.Case study
Seen in the real world.
Kestrel Union Bank is a fictional lender invented to illustrate how deductions bite. Its accounting equity looked comfortable at $2,150 million, and the executive team was preparing a dividend increase on that basis.
The regulatory calculation told a different story. After deducting $180 million of goodwill from an earlier acquisition, $70 million of software and other intangibles, and $50 million of deferred tax assets that depended on future profits, CET1 came out at $1,850 million, some 14% lower than the headline equity figure.
In this illustrative case the board learned two things: that capitalising software development flatters accounting equity but does nothing for regulatory capital, and that retained earnings are the cheapest source of CET1 available. The dividend increase was trimmed and the growth plan rephased.
Watch out
Common mistakes.
- Treating CET1 as the same thing as book equity. Regulatory deductions such as goodwill, intangibles and some deferred tax assets can reduce it materially below the balance sheet figure.
- Confusing CET1 capital with the CET1 ratio. The first is a dollar amount of capital; the second divides that amount by risk-weighted assets to show adequacy.
- Assuming preference shares or subordinated debt count. Those instruments fall into Additional Tier 1 or Tier 2, not into CET1, because they carry repayment or coupon obligations.
Questions
People also ask.
Why is goodwill deducted?
Because it has no value in a failure scenario; it cannot be sold to cover losses, so counting it would overstate the bank's real cushion.
How does a bank increase CET1?
Mainly by retaining profits, issuing new ordinary shares, reducing deductions or shrinking risk-weighted assets by selling higher-risk exposures.
Does CET1 apply to non-banks?
The formal definition is a banking regulation concept, though insurers and investment firms face comparable capital regimes with their own definitions of core equity.
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