More than 160 migrants travelled across the Channel in small boats in 24 hours - a record for a single day.
The Border Force intercepted seven boats on Wednesday, while 11 men were detained on a beach at Samphire Hoe in Kent.
There were 166 migrants in total, including one boat which had 48 males and 16 females who presented themselves as Iranian, Iraqi, Kuwaiti and Afghani.
The Home Office said they have all been taken to Dover to be assessed.
Previously the most migrants attempting to cross the Channel in a day was 145, on 8 May.
As well as the boat with 64 people on board, a second vessel earlier was carrying a group of 14 males, and a third had a group of 17 males and females.
Two more boats were carrying 16 males each, with one group presenting themselves as Iraqi, Kuwaiti, Iranian and Syrian.
A sixth boat was carrying a group of 13 males who presented themselves as Iranian and Iraqi nationals, and a seventh was carrying a group of 15 males who presented themselves as Iranian, Iraqi, Yemeni, Syrian, and Chinese.
In the eighth incident, a group of 11 males, who presented themselves as Yemeni and Sudanese nationals, were arrested on the beach by Kent Police.
The Home Office said the migrants would be interviewed, with transferrals to detention "where appropriate".
Immigration minister Chris Philp said: "We are determined to stop migrants putting their lives at risk, and we are working tirelessly alongside the French government to do so".
He added: "We will continue to pursue the criminals perpetrating these heinous crimes and prosecuting them for their criminal activity.
"Last year, immigration enforcement made 418 arrests, leading to 203 convictions for a total of 437 years."