The French economy grew by 0.7% in the fourth quarter of 2017, more than the 0.6% initially thought, the INSEE national statistics agency said today.
The estimate for the whole of 2017 remained unchanged at 2%.
French businesses' margins edged up to 31.8% in the fourth quarter from 31.7% in the previous three months, INSEE said.
Meanwhile, France's public deficit shrank to a better-than-expected 2.6% of gross domestic product in 2017, the first time it has fallen below the European Union's 3% limit in a decade.
The result, better than the government's 2.9% target, will be good news for President Emmanuel Macron, who made respecting EU budget rules after years of delays a cornerstone of his aim to restore French fiscal credibility among EU peers.
Shortly after he was elected last May, Macron took belt-tightening measures,
These included cuts to a popular housing allowance, to make sure the budget deficit would not overshoot the 3% limit, costing him precious points in his popularity rating.
However, figures from the INSEE statistics office showed the better-than-expected improvement in France's public finances was also in a large part due to stronger tax receipts, boosted by brisker economic growth.
The French tax burden rose to a record of 45.4% of GDP product in 2017 from 44.6% the year before.
Government spending rose by 2.5% and government revenue by 4%, INSEE said.
France was also one of only two euro zone countries still under the European Commission's excessive-deficit procedure, with only Spain expected to have done worse in 2017, according to European Commission forecasts.
The improvement should give welcome support to Macron's quest to convince Germany to reform the euro zone and help overcome mistrust between northern European countries and what they perceive as profligate southern members.
But on the domestic front, the better-than-expected deficit figures could represent a headache for the president.
Calls are growing within his party for some of the windfall, as it has come to be called, to be spent, not entirely used to pay down debt, as his government has promised.
Finance Minister Bruno Le Maire has dismissed such calls, saying France's debt, which reached 97% of GDP last year, was unsustainable.