If the offers provided by buses do not suit your needs, trains and carpooling could represent a good alternative for this distance.
Travelling by bus to Cologne from Stuttgart: how many daily connections are there?
2 bus connections exist to reach Cologne from Stuttgart per day. Please be aware that among these connections there are 2 direct lines versus zero route which have at least one change. So you will never have to take another bus.
What time are the buses to Cologne?
While the first bus leaves at 09:08, the last one leaves Stuttgart at 09:08. The duration of the journey is on average 6 hours and 35 minutes, but it can take you only 6 hours and 25 minutes with the fastest connections.
Which bus companies are in service in the route Stuttgart - Cologne?
Virail counts among its partners also Marino and Karat-S, with buses from Stuttgart to Cologne.
Marino is an Italian company mostly active in Southern Italy, but providing bus connections driving up to Northern Italy and also to France, Switzerland and Germany.