This is a 10 percent drop from its peak of 28,736 in 2014.
Ride-hailing apps Grab and Uber entered the Singapore market in 2013, and since 2014 the taxi population has been consistently shrinking.
In May, the percentage of idle or unhired taxis hit 9 percent, which is almost double what it was the same time last year.
Meanwhile, the population of private-hire car drivers has been steadily increasing.
33,000 drivers have already applied for their PDVL course so they can work as private-hire drivers.
Some 50,000 rental cars are estimated to be used as private-hire vehicles at present, which means many still have not displayed the LTA-required decal on their vehicles identifying themselves as private-hire drivers.
Taxi drivers have complained of shrinking earnings since the entry of Grab and Uber.
Some have reported an income drop of 20 percent.
Many blame taxi companies for not keeping up with changing commuter demands and improving their service offerings.