(Adds detail, analyst reaction)
ZURICH, Jan 9 (Reuters) - The Swiss National Bank expects an annual profit of 54 billion Swiss francs ($55.25 billion) for 2017, the central bank said on Tuesday, the biggest profit in its 110-year history.
The SNB anticipates an annual profit of 49 billion francs from its foreign currency positions, which have swelled to 784 billion francs by November as it sought to weaken the Swiss franc and have increased in value as the Swiss currency depreciated last year.
The bank, which will give its full earning figures on March 5, said it also expects a valuation gain of 3 billion francs on its gold holdings.
The forecast profit would be more than double the 24.5 billion francs the SNB made in 2016, and exceed its previous highest annual profit of 38.3 billion francs in 2014.
The profit is good news for the SNB in its battle against the strength of the franc, whose high value hurts Switzerland's export-reliant economy. The strategy is paying off, with the currency losing nearly 9 percent versus the euro last year.
The central bank's profit was also boosted by buoyant global stock markets. Around 20 percent of its investments are in shares of companies including big stakes in Amazon, Starbucks and Facebook.
Making a profit is not part of the SNB's mandate, which aims to ensure price stability in Switzerland while paying attention to the country's economic development. The record profit does not mean a bigger payout for the bank's 2,200 shareholders. The SNB stuck to a proposed payout of 15 francs per share - the maximum allowed under Swiss law.
The SNB is unusual among central banks in having private shareholders, although most of its shares are held by cantonal banks and the country's cantons. Its stock price more than doubled last year.
"The SNB's dividend may seem quite low when compared to its profits, but the bank was not created to make a profit. It is just a nice side effect," said Alessandro Bee, an economist at UBS.
But the Swiss federal government and the country's 26 cantons will get more cash than usual.
In addition to the normal 1 billion francs payout they get, they will share an extra 1 billion francs after the SNB's distribution reserve exceeded 20 billion francs.
Credit Suisse said the result would help the SNB to defend its expansive monetary policy, which has featured regular currency market interventions to weaken the franc.
"A large profit makes it easier for the SNB to explain why it has built up all these foreign currency reserves than if they reported a loss," said economist Maxime Botteron.
($1 = 0.9773 Swiss francs) (Editing by Michael Shields)