The 35-year-old Australian took 10 hours and 40 minutes to make the swim, landing in Calais just before 7am on Sunday. She left Abbot’s Cliff beach near Folkestone the evening before.
Ms McCardel moves to second on the list of the most Channel swims, passing the men’s record of 34 held by British athlete Kevin Murphy.
She now only trails another Briton, Alison Streeter, who has completed the challenge 43 times.
Australia’s Trent Grimsey, a former long distance swimmer, holds the record for the quickest crossing of the Channel, having completed it in six hours and 55 minutes.
Ms McCardel joked it was a “tough day at the office” after arriving in France on Sunday morning.
“I’m in great spirits,” she told PA news agency. “It’s such a joyous thing to be able to surpass the record and move to second spot on the list of most Channel crossings.
“It’s a very momentous occasion and I’m very proud to be able to represent Australia. I’ve also been thinking a lot about the people in lockdown, particularly women facing domestic violence, and I’m proud to be able to be a voice for those who don’t have one.”
Prior to the swim, Ms McCardel said she hopes her latest feat can help to raise awareness about domestic violence, revealing this week that she is a survivor who has been diagnosed with post-traumatic stress disorder.
There was initial concern as to whether Ms McCardel and her team would need to quarantine on their return to the UK, with the Department of Transport warning that the Australian should seek legal advice over the issue.
However, she said she had been given the all-clear by English and French coastguards and was now hoping to celebrate once she was back on British soil.
“I would like to have a little celebration this evening in England,” she added.
“I’m extremely lucky to be surrounded by so much love and support, from my English host to my support boat captains and crew, and I’m excited to celebrate this achievement together with them.”
Ms McCardel added that, after completing four swims in 16 days to break the record, she was looking forward to finally getting some well-earned rest.
“I’ve got a lot more muscular soreness than I anticipated, I don’t think I want to swim the Channel again for a while,” she laughed.
Ms McCardel holds multiple records for endurance swimming, including the longest ratified unassisted ocean swim in 2014, when she covered 77.3 miles in 41.5 hours in the waters around the Bahamas.
Additional reporting by PA
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