6GST - Q&A for Malaysia's GST

For Stamp (postage)

The supply of postage stamps is a taxable supply, but it is a relief supply for now(12/09/2015).

It is granted relief from charging GST from 1 April 2015 until 31 March 2016.

With effective from 1 April 2016, the supply of postage stamps is subject to GST at a standard rate.

See What is the tax code for buying stamp?

When the Postage Stamp is standard-rated:

The postage stamps for domestic delivery is standard-rated whereas the postage stamps for international delivery is zero-rated. Postage stamp for domestic delivery is GST-inclusive.

So if,

Domestic delivery, Tax code = SR, or
International delivery, Tax code = ZRE

See GUIDE ON POSTAL AND COURIER SERVICES from Custom, page 2, Q1

For Stamp duty

Tax code = OS

Stamp duty is is an out of scope supplies and does not subject to GST as the service is regulatory in nature (Peraturan Perundangan).

See GUIDE ON MONEYLENDERS, from Custom page 6, Q12.