The flow of migrants to England has caused tension between London and Paris.
The number of migrants rescued off the coast of Calais and taken in by the French state tripled in 2021, the country's Office for Immigration and Integration (OFII) said on Monday.
"The number of people shipwrecked off the coast of Calais and taken to safety was 1,002 in 2021," compared with 341 in 2020, an increase of 194%, OFII told AFP.
At least 28,395 people reached the English coast in small boats after illegally crossing the Channel in 2021, according to a tally by the PA news agency based on figures from Britain's Home Office.
That was a significant increase on the previous year when more than 8,400 people successfully made the perilous journey.
In November alone, about 6,900 people crossed the Channel to England but 27 people also lost their lives in the deadliest shipwreck on the route.
Only two people were rescued in this tragedy and they are among the 1,000 migrants taken in last year.
The rescue and care of migrants off the coast represents "a financial effort that is constantly increasing", Didier Leschi, director-general of OFII, said.
In addition, the number of people living in makeshift camps on the northern coast in the hope of crossing to Britain and who were "given shelter and directed into the national reception system was 31,103" last year, up 239% on 2020 (9,172), he added.
Among these, the proportion of people with families or who are "vulnerable" has doubled, rising from 1,158 to 2,273.
In total, OFII said, 9,779 accommodation places were offered in 2021, mainly in the Hauts-de-France region (98%) with 6,950 given a room.
The associations that help migrants in the region regularly accuse the authorities of conducting a dissuasive policy on the coast: several activists went on a hunger strike between October and mid-November 2020, to demand a moratorium on the almost daily dismantling of camps and denounce the "inhumane" treatment reserved for exiles.