Tier 1 Capital

Tier 1 capital is the core measure of a bank's financial strength from a regulator's point of view. It consists of the types of financial capital considered the most reliable and liquid, primarily Shareholders' equity. Examples of Tier 1 capital are common stock, preferred stock that is irredeemable and non-cumulative, and retained earnings.
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The sum of core capital elements (1) common shareholders' equity; (2) qualifying non-cumulative perpetual preferred stock (including related surplus); and (3) minority interests in the equity accounts of consolidated subsidiaries less goodwill and other intangible assets required to be deducted.