Spending dropped 1.4 percent in the 17-member eurozone compared with December and 1.3 percent in the 27-member European Union, the data office said.
Compared to January 2012, spending declined 7.3 percent in the eurozone and 8 percent in the EU, Eurostat said.
On an annual basis, construction outlays fell furthest in Slovenia with outlays down 22.1 percent, in Portugal with spending off 20.2 percent and in Poland with spending off 17.3 percent.
With data only complete in 13 of 27 EU countries, there were none reporting annual gains in construction spending.
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