Originally Posted by invisible

Most likely you want to be at Changi before 6AM, so you need to leave even earlier. In this case 50% surcharge applies for night time departure. Plus you might have to pay $3 surcharge for departure from the city center.

At the end you should not pay more than $25-$28. Also do not use Chisler (big black) taxi otherwise it wil cost you $15 more.