Citing a "buoyant" world environment, INSEE revised its growth estimate for 2017 upward from 1.8 percent to 1.9 percent.
"Growth has set in since the end of 2016 at a steady rate of around 0.5 percent per quarter," INSEE official Julien Pouget told a news conference, predicting that the upward trend would last through mid-2018.
The European Central Bank last week forecast growth for the 19-member eurozone at 2.3 percent for next year, a leap from its September estimate of 1.8 percent.
French GDP growth is driven by a sharply improved business climate, reducing dependence on household consumption.
But it is well shy of EU powerhouse Germany's forecast by the ECB at 2.6 percent for this year and 2.5 percent in 2018.
In especially good news for French President Emmanuel Macron, unemployment is expected to stabilise at around 9.4 percent by mid-2018, its lowest level since early 2012.
Joblessness was a constant thorn in the side for Macron's Socialist predecessor Francois Hollande, who failed to move the needle much below 10 percent during his single term in power.
Macron, elected in May, promised during his campaign to bring the rate down to seven percent by the end of his term in 2022.
- with AFP