After a shaky start to the year, Giovinazzi impressed further into the season, matching and beating Raikkonen in qualifying on numerous occasions.
The Italian ended the season 17th in the standings will return with Alfa Romeo in 2020, which Binotto says will offer more insight into the skills of the 2016 GP2 runner-up.
"Antonio may be one of the Ferrari drivers in the future, but we will first have to see how he performs next year," Binotto told Autosprint.
"Based on his performance this season, I have to be honest and say it wasn't good enough to be able to go to Ferrari. He first has to take a step for that."
After finishing second in the GP2 championship in 2016, Giovinazzi didn't sign a full-time deal with any race time until Alfa Romeo in 2019.
Binotto acknowledges that the large time Giovinazzi spent out of racing could have affected his performances, and admits that he is pleased with how he compared to Raikkonen later in the season.
"We are often very positive about Giovinazzi and that is partly due to his strong performance in 2019," Binotto said. "He has had an excellent season and has taken a big step.
"You have to remember that Antonio had not really raced for two seasons before he was allowed to join Alfa Romeo.
"From that position, it is not easy to enter Formula 1 and keep up with the competition. However, he managed to get closer to Raikkonen in the second half of the season and that is a great achievement."
Bahrain International Circuit - Winter testing