it depends on the target [1] and which Qt version you use, the default "official" Qt version usually dynamically links against Qt's libs. for windows for example you can use the msys2 version (on windows), which can also be statically linked or you could use the docker images with mxe to statically link your windows application. but you could also build a static version of Qt yourself and use that version as well.

https://github.com/therecipe/qt#targets