The loss, the biggest in the central bank's 115-year history, was caused by a plunge in the value of the SNB's investments caused by bond and stock market declines last year.
A strengthening of the Swiss franc also had a negative effect, reducing the SNB's holdings and returns from foreign investments when they were converted back into Swiss francs.
The loss, which followed a profit of 26 billion francs in 2021, means the SNB will make no payout to the Swiss central or regional governments or dividend to investors for only the second time since it was established in 1907.
Most of last year's shortfall could be attributed to the 131.5 billion francs lost on foreign currency positions, with its bond holdings losing 72 billion francs in value and its share portfolio worth 41 billion francs less.
The SNB has built up a massive balance sheet of nearly 900 billion francs as a result of buying foreign currencies during its long campaign to weaken the Swiss franc.
But the size of the balance sheet has also made the bank's performance fluctuate widely in recent years.
The reported loss wiped out the SNB's distribution reserve of 102.5 billion francs, meaning the central bank posted a net loss of 39.5 billion francs after an allocation for provisions was taken into account.
($1 = 0.9361 Swiss francs)
(Reporting by John RevillEditing by Miranda Murray and Bernadette Baum)
