Is there a sticker on the Singapore visa passport?

No stickers. Singapore no longer uses sticker visas, but uses an electronic visa system to obtain a Singapore visa. The visa will be associated with the passport, and the visa information will be electronically verified at the Singapore border control point. There will be no sticker on the passport. A visa refers to a document authorized by the government of some countries or regions to allow individuals holding the visa to enter the country or region within a certain period of time.