Mr Cotton’s selection was welcomed by a standing ovation from the 2,400 participants from 140 countries at the 44th ITF Congress in Singapore, 14-20 October 2018.
The Congress also elected the ITF's new governing executive board, which confirmed Mr Crumlin as ITF president.
Mr Cotton said: "I could not be more proud and honoured to be re-elected at the general secretary of this amazing organisation, this wonderful family.
"I will represent each and every worker of the ITF at the highest possible level, and continue the work programme we began at the last Congress to build transport workers' power."
The executive board that re-elected Mr Crumlin includes the chairs of every transport sector, women transport workers, members from the ITF regions and young transport workers.
Mr Crumlin said: "I am truly humbled to have the opportunity to continue as president of the ITF.
"The thing about the ITF is that it brings people together. Everyone in the ITF family chooses to make a difference, and they know that the ITF is the difference, the ITF can change the world for the better for everyone."