Vehicles light in a Singapore road Reuters

Singapore's retail petrol prices move in tandem with the wholesale prices, showing that the companies keep transferring the upsides or downsides in the price, according to a Competition Commission report published on Tuesday.

From June 2014 to January 2016, crude oil price fell by an average of 59 SGD cents (-67%), MOPS price fell by 52 SGD cents (-53%) and the listed price of Octane 95 fell by 35 SGD cents (-15%), the report showed.

"There appears to be a relatively high level of pass-through of the fall in MOPS price to consumers over this period," the commission said.

The country's petrol companies use Mean of Platts Singapore ("MOPS") prices, not crude oil prices in their cost accounting and pricing decisions for retail petrol.

The commission also said that there is no evidence to suggest collusion in petrol pricing, even though petrol companies monitor and react to each other's published prices.

The CCS will conduct a consumer survey on petrol demand in Singapore to understand consumer choices and switching behavior on petrol purchases.