Ennis, who had left the decision very much open after winning Heptathlon gold at the Olympics in August 2012, said she made the choice in order to focus on winning another world title.
She said: “After the incredible high of the Olympics and the post Games celebrations I went back into tough winter training with an open mind on whether or not I would want to compete indoors this year.
“Training has been going well, but I feel that my focus really has to be attempting to win another world title in Russia this summer and not the short-term indoor season.”
Head coach Peter Eriksson insisted that Ennis has the full support of UK Athletics following her decision.
“Jess is a very mature and seasoned athlete who is focused on performing at her best in major championships,” he said.
“We 100 per cent support her decision in this respect, and look forward to seeing her in action later this year in the build up to the World Championships in Moscow.”
Ennis’ first competition of 2013 is likely to be the Edinburgh Women’s League on 8 June and her first heptathlon in Tallinn, Estonia at the end of June.