* Nine-month sales up 5.9 pct at 3.33 bln euros
* Nine-month net profit up 0.4 pct at 390 mln euros
* Sees like-for-like sales down between 1-2 pct in 2012 (Adds details, CFO and analyst comments)
PARIS, Nov 8 (Reuters) - French group Legrand expects its like-for-like sales to fall in 2012, reflecting a less buoyant economy in Europe where slowing residential and construction markets have dimmed demand for its electrical fittings and switches.
The world's largest maker of switches and sockets said on Thursday its organic sales could be 1-2 percent lower in 2012, slightly below a previous forecast of flat growth in the full year.
"It's not a dynamic year, clearly. It's a year of negative organic growth for several companies," Chief Financial Officer Antoine Burel told reporters.
While markets in France, Italy and Spain are unlikely to pick up in the fourth quarter, acquisitions will compensate for the decline in like-for-like sales, he said.
Legrand expects deals to boost sales by around 4.5 percent in 2012, with margins reaching 19.5 percent, up from 19 percent previously.
Burel also told reporters that Legrand, which has acquired three companies this year, will continue to look for small deals to strengthen its position in fast-growing markets and new businesses. "There are ongoing discussions between Legrand and potential targets," he said.
Espirito Santo analyst Rob Virdee said the company has been able to deliver high margins despite a more difficult demand environment.
"Shorter term the main drawback is that Legrand is 100 percent exposed to the construction markets, which not only are still to see a recovery, but in Europe are continuing to decline," he added.
Net profit rose 0.4 pct to 390 million euros ($498 million) in the first nine months as sales increased 5.9 percent to 3.33 billion, lifted by acquisitions, the weaker euro and stronger revenues in North America, where the residential market showed signs of improvement.
Excluding acquisitions, sales fell 1.6 percent.
Shares in Legrand, which have gained around 25 percent of their value since the start of the year, were trading flat at 30.41 euros at 1030 GMT, in line with the CAC40 index. ($1 = 0.7840 euro) (Reporting by Elena Berton; Additional reporting by Gilles Guillaume; Editing by Dan Lalor and Toby Chopra)