Germany's government reportedly expects to spend 93.6 billion euros (NZ$155bn) by the end of 2020 on costs related to the refugee crisis.
The huge figure was published by weekly news magazine Der Spiegel on Saturday, citing a draft from the federal finance ministry for negotiations with the country's 16 states.
It is likely to stoke concerns, particularly among growing anti-immigration movements, on the impact of new arrivals on Europe's largest economy which took in more than a million people last year, many from Syria and other war zones.
The numbers arriving have fallen this year, helped by a deal between the European Union and Turkey that was designed to give Turks visa-free travel to Europe in return for stemming the flow of migrants.
Der Spiegel said the finance ministry's calculations included the costs for accommodating and integrating refugees as well as tackling the root causes for people fleeing from crisis-stricken regions.
Officials based their estimates on 600,000 migrants arriving this year, 400,000 next year and 300,000 in each of the following years, the report said, adding that they expected 55 per cent of recognised refugees to have a job after five years.
A spokesman for the finance ministry declined to comment on the figures but pointed to ongoing talks between the government and states, saying they would meet again on May 31 to discuss how to divide up the costs between them.
The report said 25.7 billion euros would be needed for jobless payments, rent subsidies and other benefits for recognised asylum applicants by the end of 2020.
Another 5.7 billion euros would be needed for language courses and 4.6 billion euros would be required for measures to help migrants get jobs, it added.
The annual cost of dealing with the refugee crisis would hit 20.4 billion euros in 2020, up from around 16.1 billion euros this year, the report said.
The federal government and the states are at odds over the costs of the refugee crisis and how much Berlin should pay out.