Declan Donnelly earned £5.2million for presenting by himself while Ant McPartlin was in rehab.
Ant, 44, took a break for a year to focus on his recovery following addiction issues.
As a result, Dec hosted Saturday Night Takeaway alone as well as Britain's Got Talent live shows.
Dec, 44, also presented I'm A Celebrity with Holly Willoughby, 39, who took over from Ant in 2018.
In publicly-available documents filed at Companies House, it was revealed that Dec cashed in £5,283,051 from June 2018 to June 2019.
They also show Dec raked in £14,000 a day - £1,000 a day up on the previous year.
Ant has not yet filed through his company Teecourt Limited.
The pair were reunited last year to present Britain's Got Talent together, one year after Ant crashed into two cars while under the influence of alcohol.
Ant had pleaded guilty and was subsequently fined £86,000 and given a 20-month driving ban.
Speaking to the Guardian regarding the moment he heard about the crash, Dec said that it "felt like a nightmare".
“We had a heart-to-heart. I said, ‘Look, forget everything – TV, the partnership – you’ve just got to go and get well,’" Dec explained. "I think I said I’d give everything up if he could just be happy again."
He added: "How could he do that? I wanted to punch him and hug him at the same time – and I didn’t know which one I wanted to do first.”
Ant and Dec have been back on screen over the last few months for Saturday Night Takeaway, which was thrown into chaos following the coronavirus outbreak.
The pair were forced to cancel their grand final, which is usually set in Disney World Florida.
They will also be returning to BGT this month, with the audition stages all pre-recorded. The live final, which usually airs in May, has been cancelled and will air later this year.
