Official Austrian basemap and cadastre vector tiles
The BEV (Austrian Bundesamt für Eich- und Vermessungswesen) has recently published the Austrian cadastre as open data:

The vector tile URL is:
https://kataster.bev.gv.at/tiles/{kataster | symbole}/{z}/{x}/{y}.pbf
There are 4 different style variations:
https://kataster.bev.gv.at/styles/{kataster | symbole}/style_{vermv | ortho | basic | gis}.json
When configuring the vector tiles in QGIS, we specify the desired tile and style URLs, for example:

For example, this is the “gis” style:

And this is the “basic” style:

The second vector tile source I want to mention is basemap.at. It has been around for a while, however, early versions suffered from a couple of issues that have now been resolved.
The basemap.at project provides extensive documentation on how to use the dataset in QGIS and other GIS, including manuals and sample projects:


Here’s the basic configuration: make sure to set the max zoom level to 16, otherwise, the map will not be rendered when you zoom in too far.

The level of detail is pretty impressive, even if it cannot quite keep up with the basemap raster tiles:

