More than 28,300 people crossed the Channel to the UK in small boats in 2021, triple the number for 2020.
But arrivals will continue and more people will drown in the strait between France and Britain if the government continues its “dangerous and ruthless policy”, ministers have warned.
Last year’s record number – an increase of around 20,000 on 2020 – came despite millions of pounds pledged to French authorities to tackle the problem.
The past 12 months have also seen smugglers board more and more people in bigger and bigger dinghies, sometimes with deadly consequences.
A home secretary said the government was “reforming” its approach to asylum through its new immigration plan.
The figures for small boat crossings are based on Home Office data obtained and analyzed by the PA news agency.
Between November 10 and 16, more than 3,100 people made the perilous crossing, the highest number in seven days in the current crisis.
The same month also saw a new record for a single day, with 1,185 people reaching UK shores aboard 33 boats on November 11.
In 2021, the highest number of single-day arrivals was 416, set in September 2020.
Overall, at least 28,395 people reached the UK on small boats in 2021, according to AP analysis.
Despite international efforts to crack down on the smugglers, the gangs continued to criss-cross the Strait of Dover with their murderous trade, charging thousands of pounds for a berth in flimsy inflatable boats.
The dinghies seen leaving French shores and being towed to Dover have noticeably increased in size over the past year, with some carrying up to 50 people.
This is backed up by AP data which showed an average of around 28 people traveling on every small boat arriving in the UK in 2021, up from just over 13 in 2020.
The dinghy has been compared to an inflatable swimming pool by French Interior Minister Gérald Darmanin.
Tim Naor Hilton, chief executive of Refugee Action, said UK government policy would lead to more deaths in the Strait of Dover.
He said: “People will continue to cross the Channel in flimsy boats and smugglers will continue to profit from them unless ministers open up more avenues for refugees to seek asylum here.
“[In November] we saw the deadly result of their strategy of keeping people away rather than protecting them, when at least 27 people died near our shores.
“And yet the government wants to legalize this dangerous and ruthless policy in its anti-refugee bill, which will only result in more people drowning. He needs to wake up and drop this bill now.
At least 120,441 people arrived in Europe via the Mediterranean by land and sea in 2021, according to data from the United Nations High Commissioner for Refugees (UNHCR).
At least 1,839 people are believed to be dead or missing, according to the same data.
Clare Moseley, founder of the charity Care4Calais which supports refugees living in northern France, said the growing number of small boat arrivals in Britain reflected a drop in attempts to cross by truck.
She told PA: “They are among the most vulnerable people in the world, having lost family members in bloody conflicts, suffered horrific torture and inhumane persecution.
“If the government really wanted to arrest the smugglers, it would create a safe way for people to seek asylum and put the smugglers out of business once and for all.”
Enver Solomon, chief executive of the Refugee Council, said: ‘This government needs to change its approach and instead of seeking to punish or push back people seeking safety because of the type of journey they have taken to the UK , they must create and commit to safe routes.
“As a country, we can save lives and empower people, who have already been through so much, to give back to the communities that host them.”
Home Secretary Tom Pursglove, MP, said: “Applying for asylum for protection should not involve people shopping around for asylum from one country to another, or risking their lives filling in the pockets of criminal gangs to cross the English Channel.”
Mr Pursglove added: ‘The public has been calling for reform for two decades and that is what this government is delivering through our new plan for immigration.
“The Nationality and Borders Bill will make it a criminal offense to knowingly arrive in the UK illegally and introduce life sentences for those who facilitate illegal entry into the country.
“It will also strengthen Border Force powers to stop and redirect ships, while introducing new powers to deport asylum seekers to have their claims processed outside the UK.
“MPs have already voted to reform this broken and abusive system and the sooner the House of Lords approves the Borders Bill, the sooner these reforms can be implemented.”