Singapore will no longer appear as SIN but as SGP at sporting events worldwide.
The Singapore National Olympic Council (SNOC) applied to have the code changed and the International Olympic Committee (IOC) has approved the application.
"It is official: Singapore is no more SIN but SGP at regional and international sport events," Mr Low Teo Ping, SNOC vice-president and chef de mission at the recent Rio Olympic Games in Brazil, said in a Facebook post.
The Singapore Golf Association also released the news in a brief statement on its website.
"In line with the United Nations' International Organisation for Standardisation (ISO) official 3-letter country code, IOC has approved SNOC's application to change Singapore's... code from SIN to SGP," it said.
Singapore's UN country code is SGP.
The IOC database has been modified and the new SGP code will be reflected on the IOC website and in future games, it said.
"We hope to be seeing more of SGP on the leader board of our major golf tournaments," said the Golf Association.
At the Rio Olympics, SIN was used on the results boards beside the names of Singapore athletes.
Singapore's International Air Transport Association airport code remains SIN, The Straits Times reported.
Most of the comments from readers on the newspaper's Facebook page did not approve of the change.
SGP is known as the abbreviation for the Singapore Grand Prix, one pointed out. "Why change something that is not a problem?"
How about SPG, another asked cheekily, possibly referring to the well-known acronym for sarong party girl.