* Q3 net income C$1.01/share vs C$0.82 year ago
* Q3 oper. profit C$0.85/share vs C$0.78 analysts' estimate
* Cuts capex outlook by C$850 mln
Oct 31 (Reuters) - Suncor Energy Inc, Canada's biggest oil and gas company and the dominant oil sands producer, said late on Wednesday its third-quarter net profit rose 21 percent, but it cut its capital-expenditure outlook due to a slow pace of spending on oil sands projects.
The company reported net income of C$1.56 billion ($1.56 billion), or C$1.01 per share, from C$1.29 billion, or 82 Canadian cents, for the third quarter of 2011.
Operating profit fell 27 percent to C$1.30 billion, or 85 Canadian cents per share, but beat the average forecast of analysts for 78 Canadian cents, according to Thomson Reuters I/B/E/S.
Suncor is re-examining growth plans for its massive oil sands operations in northern Alberta as its looks to cut costs and avoid the hyper-inflation that has plagued projects in the labor-starved region.
Suncor lowered its outlook for 2012 capital expenditures by C$850 million to C$6.65 billion, saying the move reflects deferred spending on non-operated projects.
"The company plans to provide updates on the timing of decisions regarding these projects when available," Suncor said in a statement.
Suncor, which also has conventional oil and gas operations in Canada, North Africa and the North Sea, as well as refineries in Canada and the United States, said its cash flow rose about 0.7 percent from the year-earlier quarter to C$2.74 billion, or C$1.78 per share.
The company's oil sands output rose about 5 percent to 341,300 barrels per day, while total average production was at 535,300 barrels of oil equivalent per day (boe/d). It also narrowed its oil sands production forecast for the year to 325,000-340,000 barrels per day.