In Stockholm the strike will affect all city centre routes as well as a number of routes in the southern suburbs.
In Västerbotten in northern Sweden, all bus drivers employed by Swedbus or Veolia also went on strike.
All public transport in Umeå immediately came to a standstill, as did half of all buses connecting different towns in the county.
The conflict between trade union Kommunal and employers group Bussarbetsgivarna has reached a stalemate and there are currently no plans for fresh talks between the parties.
“Nothing has actually happened since we reached a deadlock in negotiations with the employers on Monday,” Kommunal spokesman Stefan Köse told news agency TT.