Forbes estimates the 29-year-old singer made $185m (£148m) in pre-tax earnings in the year beginning 1 June 2018.
Swift last topped Forbes’ Celebrity 100 in 2016, when her pre-tax earnings were calculated to be $170m (£136m).
The news follows Swift accusing music mogul Scooter Braun of “stripping her of her life’s work” by acquiring her former record label Big Machine.
The bulk of Swift’s 2018/19 earnings is likely to derive from her Reputation stadium tour, which Forbes adjudged to be the highest-grossing tour in US history.
Swift’s new album Lover – her first release with her new record label Republic Records – comes out in August.
Kylie Jenner is ranked one place higher than she was last year
Social media and reality TV star Kylie Jenner is ranked second on the list with an estimated pre-tax pay packet of $170m (£136m).
Earlier this year, Jenner earned a place on Forbes’ list of the world’s richest self-made women thanks to an estimated net worth of around $1 billion (£800m).
Her inclusion on the list proved controversial, with many claiming her “billionaire” status derived in part from her famous family.
Most of her fortune derives from her best-selling beauty business.
Jenner, who turns 22 next month, was ranked third in last year’s Celebrity 100 countdown, below boxer Floyd Merryweather and actor George Clooney.
Rapper Kanye West earns third place in this year’s rundown, having made an estimated $150m (£120m) in 2018/2019.
The 42-year-old’s top-three ranking, derived in part from his Yeezy sneaker empire, comes three years after he claimed on Twitter he was $53m (£42m) in debt.
Ed Sheeran is the highest-ranked Briton in this year’s countdown
Footballers Lionel Messi, Cristiano Ronaldo and Neymar also feature in a top 10 alongside rock veterans The Eagles and TV personality Dr Phil.
Ed Sheeran, who is placed fifth in the list, is the highest-ranking Briton with estimated pre-tax earnings of $110m (£88m).
New entries in this year’s countdown include South Korean group BTS at 43, Ariana Grande at 62 and actor Paul Rudd, who is ranked joint 83rd.
The 50-year-old is adjudged to have made as much as the Rolling Stones – an estimated $41m (£32m) – in a year that saw him star in both Ant-Man and the Wasp and Avengers: Endgame.