Residents of Gauteng fear they will receive inferior services if their areas are moved to poorer provinces.
Calm
Protests over the proposed changes have taken place in recent months in several places near the borders of Gauteng province, home to South Africa's biggest city, Johannesburg.
Violence broke out on Wednesday after people assembled in the Khutsong stadium to hear the result of a decision by the National Council of Provinces, the upper house of parliament.
The NCoP approved the Cross-border Municipalities Bill, which allows government to reallocate areas from one province to another so as to get rid of municipalities that cross provincial boundaries.
In terms of the new law, government intends to make all of Merafong municipality - which includes Khutsong - part of North-West province.
Violence continued into Wednesday evening, but the area was reported to be quiet on Thursday morning.