Make Payment via:

* GIRO
* Over-the-Counter
o Cheque
o Cash
o NETS
* Self Service Kiosk
o SAM/AXS Station
* Cheque by Post
* Internet Payment
o eNETS
o vPost
o Bank's Internet Banking
* Other e-banking Services
o ATM/Phonebank Service
o Telegraghic/Fund Transfer

more detailed information in IRAS webpage

http://www.iras.gov.sg/ESVPortal/payments/payment_(menu)_iit.asp