The 54-year-old writer made the announcement on account of the 22nd anniversary of the fictional Battle of Hogwarts on May 2.
She has made it an annual tradition to apologise for killing off a character in the book, such as Fred Weasley, Severus Snape, Dobby, on the anniversary but this time she commemorated the event by donating instead.
"Today's the 22nd anniversary of the Battle of Hogwarts, but I'm going to be honest and say that it feels inappropriate to talk about fictional deaths today. Too many people are losing loved ones in the real world," she wrote on Twitter.
Rowling, whose husband Neil Murray is a doctor, said at a time when she has three frontline workers in her family, her heart goes out to all essential service providers.
"So on this anniversary of a great wizarding victory, I'm thinking of the people who're out there doing their jobs to protect us and our way of life. I have 3 key workers in my immediate family, and like all such relatives, I'm torn between pride and anxiety."
The British novelist said the money will be equally split between Crisis and Refuge charities.
"As ever in a crisis of this sort, the poorest and most vulnerable are hit hardest, so in honour of the Battle of Hogwarts, I'll be making a donation of £1m, half of which will go to Crisis, who're helping the homeless during the pandemic, and half of which will go to Refuge, because we know that domestic abuse has, sadly, increased hugely during the lockdown," she said.
Last month, Rowling revealed that she showed the symptoms of COVID-19, but had "fully recovered". She said she suffered from the infection for two weeks. RDSRDS