Recovering expenses (re-billing)
Information from: http://iras.gov.sg/irasHome/page04.aspx?id=1990
You may pay for expenses on behalf of another party (e.g. your subsidiary or customer). Subsequently, you re-bill to recover the expenses from that party.
Whether you need to charge GST on the re-billed amount will depend on whether the recovery of expenses is a reimbursement or disbursement.
Disbursement is not subject to GST. To qualify as a disbursement, all the conditions for disbursement must be satisfied. Otherwise, the recovery of expenses (commonly known as reimbursement) is considered as a separate supply made to the other party. Hence, you need to charge GST on the re-billed amount.
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