Guy LeBas, the chief fixed-income strategist for Janney Montgomery Scott, said that the number of banks that failed was within expectations. “That was give or take the number the markets were betting on,” he said. It was also positive that most of the weak banks were in Spain, a country where the central bank has a good reputation for dealing with weak institutions.

Last year, seven banks in Greece, Germany and Spain failed the tests and several others came close. But unlike the tests this year, there was no requirement for those that squeaked by to raise capital, just market pressure. The regulators argue that, since then, many banks have raised money, gotten rid of risky assets or taken other steps to become stronger, so that the fail rate this year is a sign of a stricter test.

The banks that failed or passed narrowly must now seek more capital from markets or governments. In extreme cases, they may have to be sold to other institutions or be wound down.

But it will be up to national governments and the banks themselves to find additional capital.

In a statement, European banking regulators said they were “aware of the funding liquidity challenges in the current environment, and national authorities are taking steps to extend maturities, increase buffers and develop contingency plans.” The banks that failed were Volksbanken in Austria, the Greek banks EFG Eurobank Ergasias and Agricultural Bank of Greece and five in Spain: Banco Pastor, Caja de Ahorros del Mediterraneo, Banco Grupo Caja3, CatalunyaCaixa and Unnim.

The overall shortfall for the eight was 2.5 billion euros ($3.54 billion).

The 16 banks that passed narrowly were concentrated in Spain, Greece and Portugal. The more prominent names included Banco Popolare in Italy and Banco de Sabadell in Spain. The list also included two German landesbanks, Norddeutsche Landesbank and HSH Nordbank.

Deutsche Bank said in a statement that its so-called core Tier 1 capital, the most resilient form of reserves, fell to 6.5 percent under the worst-case stress assumptions. For Société Générale, the comparable figure was 6.6 percent and for UniCredit it was 6.7 percent.