The Monegasque driver finished ahead of Vettel with more wins and pole positions, but when asked whether at the start of the year if he’d believe it if someone told him he’d beat his team-mate, he said he wouldn’t have.
“No, no I didn’t have that confidence,” Leclerc said after the race in Abu Dhabi.
“I always thought that if I did the job correctly success would come, but I mean Seb is a four-time World Champion, so it would have been difficult to believe it.
“I’m very happy with my first season. There’s been regrets and mistakes, but I’ve learned from the mistakes and I’m sure it will be useful for 2020 to have a better season.”
Leclerc held off Valtteri Bottas to finish the final race of the season on the final step of the podium and, in the on-track interview afterwards, he paid tribute to Vettel.
“I’ve learned a huge amount thanks to Seb,” he added.
“It’s been a great year, a realisation of the dream since I was a child to be with Ferrari and in Formula 1 and it’s up to me to get better and give them the success they deserve.”