You sell 40 mobile phones to a GST-registered retailer for S$12,000. You add no GST to the invoice. Your buyer declares the GST instead. This is customer accounting, which has applied since 1 January 2019.
The goods covered
– Mobile phones with a screen of 17.5 cm or less
– Memory cards
– Off-the-shelf software
IRAS defines each category in detail. Read the 10th edition of its customer accounting guide (30 January 2026) before you decide a product is in or out. Check the exact meaning of off-the-shelf software before you rely on the name alone.
When the rule applies
Two tests must both be met. The buyer is GST-registered, and the supply is worth more than S$10,000 before GST. A sale of exactly S$10,000 stays outside the rule.
The numbers
You sell 40 phones at S$300 each. This is S$12,000, which is above S$10,000, so customer accounting applies. You charge no GST. Your buyer declares output tax of 9%, which is S$1,080. A buyer who uses the phones to make taxable supplies claims the S$1,080 as input tax, so the cash effect for this buyer is nil. A buyer who also makes exempt supplies recovers only part of the S$1,080 and bears the rest.
Now sell 30 phones at S$300. This is S$9,000, below the S$10,000 limit. Normal GST applies. You charge S$810 and pay this amount to IRAS.
What changes for you as the seller
– Check your buyer’s GST registration before you invoice. A buyer without registration pays normal GST.
– Make sure your invoice shows the sale falls under customer accounting. Look up the exact wording in the IRAS guide.
– You no longer hold the buyer’s GST in your bank account, so you have nothing to pay over on this sale.
– Review last quarter’s sales ledger for sales of these goods above S$10,000 and check how you invoiced each one.
– Keep a copy of the buyer’s GST registration number with each invoice, and keep the file for 5 years.
What changes for you as the buyer
– You declare the output tax on your own GST return, even though the invoice shows no GST.
– Leaving the amount out understates your GST.
– You claim the matching input tax only to the extent your purchase supports taxable supplies.
Why the rule exists
The rule sits beside IRAS work on missing trader fraud, where a supplier collects GST and never pays the tax over. Moving the declaration to the buyer closes this gap for goods popular in such schemes. If you trade in these goods, read my article on missing trader fraud as well.
Send your latest profit figure or your question by WhatsApp to +65 9876 3553 or by email to henry@cschow.com.sg.
Henry Chow
Public Accountant, C S Chow & Co