What it means
Regulators split bank capital by how reliably it absorbs losses. Tier 1 is going-concern capital, which soaks up losses while the bank continues to operate; Tier 2 is gone-concern capital, which protects depositors and senior creditors during a wind-up but does nothing to keep a struggling bank open.
Tier 2 exists because it is cheaper than equity. Issuing subordinated bonds lets a bank strengthen its total capital position without diluting shareholders, and the interest is a predictable cost rather than a claim on profits.
That makes it an attractive way to meet the total capital requirement, provided the Tier 1 layer underneath is already sufficient. The qualifying rules are strict.
Instruments must be subordinated to depositors and general creditors, have an original maturity of at least five years, carry no incentive for the issuer to redeem early, and be free of covenants that would accelerate repayment. Regulators also cap how much general loan loss provisioning can be counted, so a bank cannot simply provision its way to a stronger ratio.
The rule that catches people out is amortisation in the final five years. During the last five years before maturity, a subordinated instrument is recognised on a straight-line basis at 20% less each year, so a bond with three years left counts for only 60% of its face value.
Treasury teams therefore plan replacement issuance years ahead, because capital can quietly disappear while the debt is still fully outstanding and still paying interest. The practical point for anyone reading bank results is that a healthy total capital ratio propped up by Tier 2 is not the same as a strong bank.
Analysts look at CET1 first, then at how much of the total is supplementary, because Tier 2 offers no protection at all to a bank trying to trade through a bad year.
In practice
Real-world examples.
Example
A bank approaching its total capital minimum issues $800,000,000 of ten-year subordinated notes rather than raising equity. The total capital ratio improves without diluting existing shareholders, though the CET1 ratio is unchanged and analysts note that the underlying quality of capital has not improved.
Example
A treasury team notices that $1,200,000,000 of subordinated debt will begin amortising for capital purposes in eighteen months, losing 20% of its recognised value each year. It schedules a replacement issue well before the erosion starts, avoiding a scramble in unfavourable markets.
Example
A rating agency reviewing a mid-sized lender highlights that Tier 2 makes up a fifth of total capital while the CET1 ratio sits only slightly above the buffer. The agency keeps the outlook negative despite a total capital ratio that looks comfortable on the face of it.
Think of it
“Tier 2 is your backup capital-supplementary capital that protects in wind-down situations.
Formula
Calculation
Total capital ratio = (Tier 1 capital + Tier 2 capital) / risk-weighted assets
A bank holds Tier 1 capital of $12,000,000,000 against risk-weighted assets of $100,000,000,000. Its Tier 2 items comprise $2,700,000,000 of qualifying instruments with more than five years to run, plus $500,000,000 of subordinated notes that now have only three years left to maturity.
Because those notes are inside the final five years, they amortise at 20% a year, so only 3/5 of the face value counts: $500,000,000 x 60% = $300,000,000, with $200,000,000 excluded. Recognised Tier 2 capital is therefore $2,700,000,000 + $300,000,000 = $3,000,000,000.
Total capital is $12,000,000,000 + $3,000,000,000 = $15,000,000,000, giving a total capital ratio of $15,000,000,000 / $100,000,000,000 = 15%. Against the Basel III minimum total capital requirement of 8%, the bank needs 8% x $100,000,000,000 = $8,000,000,000, leaving a surplus of $15,000,000,000 - $8,000,000,000 = $7,000,000,000. Twelve months later, with those notes down to two years remaining, they would count at only 40%, or $200,000,000, cutting recognised Tier 2 by a further $100,000,000 with no cash having changed hands.Case study
Seen in the real world.
Brackenhall Trust Bank is an illustrative, fictional lender that reported a total capital ratio of 15% and used the figure prominently in its investor presentation. Beneath that headline, $3,000,000,000 of its $15,000,000,000 total capital was Tier 2, and a large slice of it was subordinated debt drifting into its final five years.
Over the following two years, in this fictional scenario, amortisation stripped recognised Tier 2 down even though not a dollar had been repaid, and a weak credit cycle ate into retained earnings. The total capital ratio slid towards the requirement, and because the shortfall was in supplementary capital the board could not fix it quickly with retained profits alone.
Brackenhall ended up issuing new subordinated notes into a nervous market at a materially higher coupon than the ones they replaced. The illustrative lesson is that Tier 2 has a shelf life, and a capital plan that ignores the amortisation schedule is planning to refinance at the worst possible moment.
Watch out
Common mistakes.
- Treating Tier 1 and Tier 2 as equally protective, when only Tier 1 absorbs losses while the bank is still operating.
- Ignoring the straight-line amortisation of subordinated debt in its final five years, so recognised capital falls while the debt remains fully outstanding.
- Judging a bank on its total capital ratio alone, without checking how much of that total is supplementary rather than common equity.
Questions
People also ask.
What actually counts as Tier 2 capital?
Mainly subordinated debt with an original maturity of at least five years, certain general loan loss provisions up to a regulatory cap, and some revaluation reserves.
Why would a bank issue Tier 2 instead of raising equity?
Because subordinated debt is cheaper than equity and does not dilute shareholders, so it is an efficient way to meet the total capital requirement once Tier 1 is already adequate.
Does Tier 2 capital protect depositors?
Yes, but only in a failure, since it ranks below depositors and senior creditors in a wind-up and provides no cushion for a bank trying to keep trading.
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