European regulators say eight banks have failed a “stress test” showing they need to build a bigger financial cushion in case of another recession or other problems.

Most of the banks are in Spain, while others are in Greece and Austria.

The European Banking Authority says the institutions need to have readily available capital equivalent to about five percent of the loans they have made. It will take about $3.5 billion to bring them up to that standard.

Another 16 European banks barely passed and are also being urged to bolster their reserves in case a default by Greece or other serious financial problems cause losses in the banking sector.

Inadequate reserves are one reason that some firms failed during the financial crisis.