The ELY Centre does not collect and maintain data on past speed limits because the limits can vary greatly due to road work, for example. We also do not find out and give statements on what the current speed limit is at a particular road section or when the speed limit in question was set. The road maintenance authority does not have enough resources for these kinds of analyses. In accordance with the law, the speed limit marked on the traffic signs must be followed. The speed limit takes effect immediately after the traffic sign is posted. If there are no traffic signs to indicate the speed limit of a particular road section, the general speed limit of 80 km/h applies.

Typically, speed limits are lowered before the winter to prepare for the dark season and winter conditions, and the normal, higher speed limits are taken back to use in the summer. The lower winter speed limits are usually posted in late October and the higher summer speed limits in early April. Speed limits can be changed at other times as well, if the road condition, traffic, land use or other local circumstances change. The effect of the driving speed on the safety and smoothness of traffic are taken into account when setting the speed limit. Regional contractors are responsible for posting and removing speed limit traffic signs.

Lower speed limits are normally also used near roadworks sites because of both the exceptional traffic arrangements and the work site safety. The speed limits of roadworks sites are based on the national instructions on the traffic arrangements at roadworks sites, issued by the Finnish Transport Infrastructure Agency. The speed limits are returned to normal when the entire site is completed. The construction company is responsible for posting and removing the speed limit signs of roadworks sites.