* Q3 net profit 433.3 mln riyals vs 317.2 mln yr-ago
* Beats average in Reuters analyst poll of 398.9 mln riyals
* Early result season trend of strong bank profit growth (Adds context and background, Alinma results)
RIYADH, Oct 7 (Reuters) - Saudi Hollandi Bank beat forecasts with a 37 percent rise in third-quarter net profit, joining rivals in benefiting from rising lending, deposits and dealmaking in an economy buoyed by years of high oil prices.
Saudi Arabia's eighth-largest listed bank said on Monday it made 433.3 million riyals ($115.5 million) in the three months to Sept. 30, topping the average forecast of 398.9 million riyals in a Reuters poll of five analysts.
Operating income climbed 16 percent to 667 million riyals, while profit from special commissions grew 20 percent to 433 million riyals, it said, without elaborating.
Saudi companies issue brief earnings statements early in the reporting period before publishing more detailed filings later.
The kingdom's banks are benefiting from a robust economic backdrop, with years of high oil prices and government surpluses pushing state spending to record levels.
Earlier on Monday, Riyad Bank, Saudi Arabia's third-largest listed lender, registered a 18.8 percent rise in quarterly profit.
Meanwhile, Alinma Bank said on Monday its third-quarter net profit advanced 33.7 percent year-on-year.
Saudi Hollandi's loans portfolio stood at 53.67 billion riyals at the end of September, 23 percent higher than the same point of 2012.
While at a nine-month low in August, bank lending to private companies still grew at a rate of 15 percent, according to central bank data.
Saudi Hollandi's deposit base gained 16 percent year-on-year to 61.4 billion riyals.
$1 = 3.7501 Saudi riyals Reporting by Angus McDowall; Editing by David French and Mark Potter