At 0231 GMT, shares of ComfortDelGro were 2.6 percent higher at S$1.385 with 967,000 shares changing hands.
"Investors may be buying into the stock now in anticipation of good earnings results, which they will announce on 14 November," said a local trader.
ComfortDelGro is expected to benefit from the Singapore government's push to encourage more people to use public transport and cut the supply of certificates of entitlements(COE), which would make car ownership expensive.
"We see better penetration for public transport in Singapore and expect ComfortDelGro to benefit from ridership growth and lower fuel cost pressures," said Lee Wen Ching, an analyst at CIMB Research.
The company's relatively stable earnings growth and attractive yield of about 4 percent is also a draw for investors, analysts said.