Sending a migrant to Rwanda or another "safe country" would cost £63,000 more than keeping them in the UK, according to the government.
An individual's relocation would cost a total of £169,000, according to an economic impact analysis of the illegal immigration bill being considered by Parliament.
However, because they would no longer need housing support, there would be a savings of about £106,000.
According to the government, the policy would also serve as a deterrent.
According to the Home Office assessment, preventing someone from entering the UK illegally would not incur any costs.
Although it stated that the potential savings were "highly uncertain," it provided a range of estimates for each individual of between £106,000 and £165,000.
By prohibiting anyone entering the UK illegally from requesting asylum, the bill aims to stop people from navigating the English Channel in small boats.
Instead, they would be imprisoned and transported to Rwanda or another "safe country," whichever they preferred.
"Our impact assessment shows that doing nothing is not an option," said Suella Braverman, the home secretary.
"We cannot support a system that encourages people to pay people smugglers to enter this country illegally, risk their lives, and put an unacceptable burden on the UK taxpayer.
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