The fund in late January informed 20,000 people that it if they failed to pay off their outstanding contributions for 11 to 12 months, it would take action to recover the money, Sodra Director Mindaugas Sinkevičius said.
"We will not apply recovery sanctions until we assess the data on all 20,000 (people)," he said in a news conference.
According to Sodra, around 300,000 people owe compulsory health insurance contributions for at least a month. All of them will be urged in writing to pay off the arrears or submit the necessary documents to have their debt annulled.
Outstanding compulsory health insurance contributions total 80 million euros, including around 50 million euros in long-term arrears for a year or more.
"Those insured in other EU countries, as well as Norway and Switzerland, have until the end of February to submit documents proving that," Sinkevičius said.
The debtors are Lithuanian nationals who have left the country but have not deregistered, as well as those who are not in employment or studying, and those who have registered as self-employed, he said.