Singapore CPI tumbled in August, falling 0.8% compared to levels a year earlier.
The figure, well below expectations for a decline of 0.5%, marked the fastest pace of deflation since October 2009.
Costs for private road transport and accommodation decreased by 2.9% a piece according to Statistics Singapore.
Elsewhere services inflation increased by 0.5%, down from 0.6% in August, while the cost of retail items fell 0.6% having come in flat in the year to July.
Food inflation rose 1.9%, unchanged from the previous month.
Excluding volatile items such as accommodation and private road transport, prices increased 0.2% from a year earlier, just half the increase recorded in the 12 months to July.
Understandably given the big downside miss, the Singaporean dollar has weakened on the news, falling 0.52% against its US counterpart to 1.4236.
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