A majority of European banks with more than €100 billion in assets posted a quarter-over-quarter increase in fully loaded common equity Tier 1 ratio in the third quarter, according to data from S&P Global Market Intelligence.

Of 36 banks in the sample, 19 reported an increase in CET1 ratio, with Norway's DNB ASA posting the biggest quarterly improvement of 97 basis points to 18.27% in the period. U.K.-based Lloyds Banking Group PLC, meanwhile, endured the largest quarterly decline in the ratio, shedding 50 basis points on a quarterly basis to 13.17%.

Britain's Nationwide Building Society led the table with a ratio of 31.28% in the third quarter, followed by OP Financial Group with a ratio of 19.60%. Spanish lenders Banco Santander SA and Banco de Sabadell SA reported the lowest ratios of 11.30% and 11.37%, respectively, in the period.

The ratio quantifies a bank's CET1 capital as a percentage of risk-weighted assets, and banks in the region must have a fully loaded CET1 ratio of at least 7% from 2019 onward under Basel III regulations, comprising a minimum 4.5% CET1 ratio and a 2.5% capital conservation buffer.

Read more data-led stories about European banks' capital and liquidity coverage ratios.

Liquidity coverage ratios at Europe's largest banks in Q3

Leverage ratios at largest European banks in Q3