The pandemic hit demand but lower wholesale prices helped offset this, Endesa said, adding it expected no additional significant impacts in the second half of the year.
The company, which is controlled by Italy's Enel, reported a net profit of 1.13 billion euros (1.03 billion pounds) versus 776 million a year earlier.
Excluding the savings from the collective-bargaining deal, net profit would have been 861 million euros, the company said.
Endesa will maintain its dividend policy, it said.
(Reporting by Inti Landauro; editing by Jason Neely)