Singapore registered motor vehicle must have at least thee-quarter tank of motor fuel inside their vehicle motor fuel supply tank when departing Singapore. This Three-Quarter Tank rule applies to both the petrol and CNG supply tank of Singapore-registered vehicles departing Singapore. Drivers should ensure that the petrol fuel tank and the CNG fuel tank are both at least three-quarter full when departing Singapore.
Failure to do so constitutes an offence. On settlement of the offence, you will have to turn back to top up your fuel if you wish to continue on the journey.
Please find further information on the Three-Quarter Tank Rule at Singapore Customs website.