Maps and plans, and the digital datasets on which they are based, are only useful if they are kept up to date and are legally binding. It is therefore essential to ensure that the data are updated. This also applies to the cadastral surveying: in accordance with the applicable legislation, all data relating to property boundaries, buildings, individual objects such as retaining walls and shelters, as well as building addresses and various other details, must be kept up to date. 

If the legal or factual circumstances should change, the relevant surveyor (depending on the region, this may be an updating, district or municipal surveyor) has to survey and update the change(s). 

There are two types of updates:

Ongoing updates

Ongoing updates reflect changes brought about by human activity.

These updates concern changes in the legal or factual circumstances, and they have to be carried out within a year after the change entered into effect. The term «changes in factual circumstances» refers to a situation in which new buildings are constructed or their layout is changed. But if a landowner wants to change the existing boundary of the property, for example by subdividing the plot, this involves a change in the legal circumstances. The costs associated with ongoing updates have to be borne by the landowner («user pays» principle). Here, the relevant cantonal authority specifies the applicable tariff for updating the cadastral surveying (though the tariff may differ from canton to canton), or the work involved is charged on an hourly basis. 

Periodical updates

Periodical updates reflect changes that take place without human intervention.

Here, examples may include a change in a forest perimeter, in the course of a river, or in a landscape as the result of a landslide or mudslide. In such cases it is not possible to identify a specific person or entity responsible, so the costs of periodical updates are shared between the federal government (60 percent) and the cantons and/or municipalities (40 percent). 

In accordance with the applicable legislation, the updating frequency for changes that are subject to periodical updating is a maximum of twelve years.