Each Syrian refugee is set to cost the taxpayer up to £23,420 in the first year of their relocation to the UK, figures seen by BBC News suggest.
The Home Office has confirmed the figures, contained in a briefing document from an Essex local authority, are accurate.
An adult benefit claimant from Syria costs up to £23,420, or £10,720 if they were able to work, the document said.
The government has pledged to take in 20,000 Syrian refugees by 2020.
It has also provided £1bn in aid to Syria, with an extra £100m given to charities to help thousands displaced by the conflict.
More than 11 million people have left their homes in Syria as a result of fighting between President Bashar al-Assad's forces and those opposed to his rule, as well as jihadist militants from the so-called Islamic State. Thousands of these people have since been making their way to European countries, including the UK.
The Home Office document suggests the cost to the taxpayer of taking in Syrian children ranges from £10,720 for under-threes to £16,220 for those between the ages of five and 18.
The cost per Syrian refugee to local councils is estimated to be £8,520 per person, along with costs of £12,700 for benefits and £2,200 for medical care to be funded by central government.
Another document seen by BBC Essex, entitled Syrian Resettlement Scheme - Funding Process, states the government will give each council £8,520 per refugee.
The figures suggest central government will cover the full cost to local authorities - but some politicians have warned this will not be the case.
The document states that the Home Office has based its estimated costs on the government's current resettlement schemes for Gateway - refugees the UK takes through the United Nations - the VPR (Vulnerable Persons Relocation) scheme and the Afghan resettlement programme.
The Home Office document notes that "these [resettlement programmes] are significantly smaller than the proposed extension to VPR and do not always provide helpful data to allow us to set a unit cost at a level which gives us confidence".
Leading former judges and lawyers have criticised the government's response to the crisis, calling it "slow and narrow" and saying the offer to accept 20,000 refugees over five years is not enough.
And 84 Church of England bishops have written to Prime Minister David Cameron, urging him to accept at least 50,000 Syrian refugees.
Thurrock Council leader John Kent accused the government of not covering the full cost to local authorities of taking on the Syrian refugees.
Mr Kent said: "There are significant costs attached to caring for unaccompanied children. Currently the government only funds 60% of those costs - the rest is picked up by the local council."
The Labour councillor said Thurrock would not be offering to take any Syrian migrants.
Edinburgh and Glasgow councils have pledged to take about 100 Syrian refugees, Newcastle and Birmingham up to 50 and Southend about 10.
Southend told the BBC it had offered to take three families, with the cost in the first year looking set to be over £100,000. Other councils in Essex say they are likely to take between six and 10 but are still talking to government agencies.
Last week, Essex County Council voted unanimously to call on the government to fully fund Syrian refugees for five years rather than just the first year.
In a letter to local council chief executives, the Home Office said it would "also provide additional funding to assist with costs incurred in future years" and that "these arrangements will be applied to all cases since the 20,000 expansion was announced".
The detail of what this funding will be is still to be announced.
Jonathan Carr-West, of the Local Government Information Unit think tank, said it was "good to see" that a commitment from several councils to taking in refugees was to be matched by funding from central government.
But he said: "The complexity of local authority funding and the unpredictable knock-on effect on other services suggest that for some councils, the extra money may not cover all their costs."
He also said local authorities had a "crucial role" in mobilising communities to provide support to those "fleeing danger and persecution".