A rise in government spending for a record influx of asylum seekers was also a major factor for growth.
Gross domestic product expanded 0.3 percent for the three months ending September, the Federal Statistics Office Destatis said, confirming its earlier estimate.
Household consumption rose 0.6 percent from the previous three months, while state spending shot up 1.3 percent.
The strong domestic consumption made up for weakness in companies' investments, which fell 0.8 percent compared to the previous quarter due to a cloudy outlook for both emerging markets and eurozone economies.
Imports were up sharply, rising 1.1 percent, while exports grew only 0.2 percent.
The latest figures suggest that Germany is no longer just an export-oriented economy, but that consumption is fast becoming a key pillar of output.
Public spending is further set to rise in coming months, as the state pays for lodgings, food and education for the one million new asylum seekers Germany expects this year alone.
Berlin has budgeted €8 billion in additional spending for refugees for 2016.
Economists and politicians have said that the extra spending would be a bonus for the economy.