The Swiss' spot at the tournament in London was confirmed following the release of the draws for next week's ATP competitions in Stockholm, Vienna and Moscow.
Wawrinka's prospective appearance at the Finals – which will be the second of his career – caps a year that saw him end his wait for a maiden grand slam title with victory at the Australian Open in January, reaching a career-high ranking of third as a result.
And the 29-year-old, who now sits at number four in the world, is understandably thrilled to have achieved his aim of a second straight qualification and is relishing returning to the O2 Arena.
"I'm extremely happy to be back in London," Wawrinka said.
"It was my dream and goal to qualify again this year after the great experience in 2013. It's only my second time at the Barclays ATP World Tour Finals and being part of this great event remains a childhood dream for me.
"The atmosphere in London is one of a kind and it means a lot to me to be there together with the very best players of the world."