Abdul Ezedi was found just beneath Chelsea Bridge two and a half weeks after throwing a corrosive substance at the end of January.
Officers had been looking for the 35-year-old, who was from Newcastle, all that time.
Senior coroner Mary Hassell ruled out the possibility that Ezedi was pushed or fell into the water by accident and ruled he died from suicide and drowned.
She told the inquest at Poplar Coroner’s Court in east London: “The circumstances surrounding his death are clear in part.
“The evidence of the Metropolitan Police Service is that he is likely to have entered the River Thames at Chelsea Bridge at approximately 11.30pm.
“It seems likely to me that he drowned almost immediately and, although he was not found until 19 February 2024, I will put his death as 31 January.”
A huge manhunt saw detectives track Ezedi’s final movements along the river on CCTV.
It came after his former girlfriend was doused with a corrosive chemical in an attack on her and her daughters, aged three and eight.
After Ezedi, from the Newcastle area, fled the scene, he was captured on CCTV with what appeared to be serious injuries to his face.
Ezedi initially used his bank card to travel on the Tube before walking a route that broadly hugged the banks of the Thames in the following hours.
In the days after the attack it emerged Ezedi was granted asylum in the UK in 2020.
This was despite the fact he was handed a suspended sentence for a sexual offence in November 2018.