At least 430 migrants crossed to the UK onboard just 14 small boats on Monday.
The Home Office confirmed the number of arrivals, believed to be the highest in a single day.
It adds to the more than 1,850 people who have crossed to Britain on board vessels so far this month, more than the total for the whole of 2019.
Dozens of people, including women and young children, were seen arriving at Dungeness.
It came after 241 people arrived in the UK on Sunday on board eight boats - as 2021 continues to see rising numbers of crossings.
A boat of more than eight migrants is seen crossing the Channel on Tuesday morning
Some of the migrants raised their hands in celebration as they stood on the beach, while others sat down on the shingle shoreline amid 24C sunshine.
The large dinghy is believed to have left northern France or Belgium earlier on Monday before crossing the dangerous 21-mile Dover Strait.
Border Force and Kent Police were in attendance at the scene as they awaited the arrivals on Monday afternoon.
The black dinghy came ashore on Dungeness Beach, around 30 miles along the coast from the port of Dover.
The vessel had been watched by the RNLI as it got closer and closer to the coast before eventually landing on the beach at around 1pm.
Among the arrivals were women and children, some too young to walk.
More people are believed to have attempted the cross to the UK on Monday, with Border Force and French warships active in the English Channel.
Dan O’Mahoney, Clandestine Channel Threat Commander, said: “There is an unacceptable rise in dangerous small boat crossings across the channel because of a surge in illegal migration across Europe.
“People should claim asylum in the first safe country they reach and not risk their lives making these dangerous crossing. We are continuing to pursue the criminals behind these illegal crossings.
“Police patrols on French beaches and enhanced intelligence sharing between our security and law enforcement agencies has helped to prevent crossings through a combination of inland and sea patrols.
“The government continues to undertake substantial steps to tackle the unacceptable problem of illegal migration through the Nationality and Borders Bill which will protect lives and break this cycle of illegal crossings. The government is also continuing to return those with no legal right to remain in the UK.”