Increased infection rates mean that travelers from certain countries are affected by the self-isolation requirement.
Finland again restricts border traffic, as the second wave of the epidemic strikes some European countries.
As of Monday 27 July, travelers returning to Finland from Austria, Slovenia and Switzerland are now obliged to self-isolate for 14 days because coronavirus cases have been rising in those countries recently.
Finland's criteria for dropping the self-isolation requirement include a maximum of eight new infections per 100,000 people during the previous two-week period.
Rising infection rates in Algeria and Australia meant that those countries were also affected by the restrictions and self-isolation requirement.
Restrictions have meanwhile been extended for travel to Finland from the Czech Republic, France, Luxembourg, Poland, Portugal, Spain and Sweden.
States with sufficiently low infection rates not to require self-isolation include Belgium, Denmark, Estonia, Germany, Greece, Hungary, Iceland, Italy, Latvia, Liechtenstein, Lithuania, Malta, the Netherlands, Norway and Slovakia.
Finland eased travel restrictions for many European countries starting on July 13.
So far, Finland has reported 329 deaths associated with the novel coronavirus and 7,398 infections.