Effective 1 January 2023, Singapore will be extending GST to B2C imported non-digital services and goods imported via air or post that are valued up to (and including) the current GST import relief threshold of S$400. Non-resident providers of non-digital services and imported low-value goods can register under the Overseas Vendor Registration regime which is already available for non-resident providers of digital services.
B2C includes transactions made by a GST-registered person, to a non-GST registered customer. For B2B transactions a reverse charge procedure will apply, meaning that purchasers will be liable to self-assess GST on their purchases of low value goods and imported services.
The updated IRAS e-Tax guide can be found here.