A man alerted the police last Tuesday after he discovered a $10,000 Orchid Series note he had bought online was a fake.
On Thursday, officers from the Commercial Affairs Department arrested two suspects, aged 34 and 55, who were believed to be the sellers of the note.
Police believe the 34-year-old suspect had bought the counterfeit $10,000 Orchid Series note this month from an unknown seller in Batam, Indonesia.
He and the other suspect are believed to have sold the note online to the buyer for $11,500.
Police seized the note, as well as two T-shirts, a receipt, three mobile phones and a total of $1,200 as case exhibits.
Those convicted of using counterfeit currency notes as genuine notes may be jailed for up to 20 years and fined.
The police reminded the public to remain vigilant and examine all $10,000 Orchid Series notes carefully as they are not commonly available and in circulation.
Readers can refer to the Monetary Authority of Singapore's website for descriptions and images of the Orchid Series notes.
The police reminded the public to report any counterfeit currency, note the description and features of the person presenting the note, and to limit the handling of the counterfeit currency in possession.