Scientists warned late last month that it was on track to become the world's hottest month on record.
This year has been the third-warmest year to date, Copernicus deputy head Samantha Burgess said.
"We just witnessed global air temperatures and global ocean surface temperatures set new all-time records in July," she said.
"It shows the urgency for ambitious efforts to reduce global greenhouse gas emissions, which are the main driver behind these records."
June had also smashed through the previous temperature record for that month, according to Copernicus, which bases its calculations on a dataset going back to 1950.
Sweltering temperatures have affected considerable swathes of the planet, with heat records registered from Death Valley in the U.S. state of California to a northwest China township as Canada and southern Europe battle wildfires.