Charles’ rallying cry came on the eve of England’s historic showdown with Spain at the Stadium Australia in Sydney.
“Good luck today Lionesses, and may you roar to victory,” Charles said in a message posted on social media on Saturday.
Queen Letizia of Spain is set to travel to Australia for the final, while UK royals are staying at home.
Both Prince William and prime minister Rishi Sunak will also not be attending the game.
But it is understood that Charles and the Queen will be among the millions of Britons following the game from afar on Sunday.
A Buckingham Palace source said: “Both Their Majesties will be following Sunday’s events with the greatest interest.”
The Prince of Wales has wished the Lionesses “good luck” for the final, and apologised for not being in Australia to watch them in person.
In a video message posted on social media, William, who was sat next to daughter Charlotte, also said he was proud of what the team had achieved.
In a letter, Mr Sunak wished England boss Sarina Wiegman and her players good luck for the final in Sydney, Australia, on Sunday, telling them: “You’ve made us all proud.”
Mr Sunak has opted not to attend the southern hemisphere final in person, sending foreign secretary James Cleverly and culture secretary Lucy Frazer to Australia to represent the UK government.
Addressing the letter to “Sarina and all our Lionesses”, the prime minister said: “On behalf of the entire country, I want to wish you the best of luck against Spain in the World Cup final!
“Once again, this summer, you’ve made us all proud.
“From beating the Aussies in their own backyard to winning that penalty shoot-out, you have inspired us with your skill, teamwork and courage.
“This weekend, like millions of others, I will be watching and cheering you on.
“But whatever the result, I want you to know that you have already secured a lasting legacy: that every girl in this country will have equal access to all school sport, including football.”
Mr Sunak, a Southampton FC supporter, continued: “For my daughters, and for every girl in this country, you have made football something for them; you have made them feel they belong on the pitch.
“So – in a way – you’ve already brought football home.
“All that remains is to bring the trophy home too — and the whole nation is rooting for you. Thank you – and good luck!”
