Health insurance companies have over €3.3bn in surplus reserves which they could use to cut premiums, consumer lobby group Consumentenbond said on Wednesday.

The association says figures from 2015 show the four big insurers – CZ, VGZ, Achmea and Menzis – saw their net profits halve last year. But at the same time, the big four added €307m to their reserves.

Of the €3.3bn set aside as reserves, €1.4bn is in the hands of Achmea.

The association said the insurance companies should do ‘all they can to limit premium increases’ and to act responsibly. ‘What has gone up in price, what reserves do they actually have and what have they done to keep increases to a minimum?,’ the organisation said.

Health minister Edith Schippers said in September she expects premiums to rise by an average of €3.50 a month next year.