How to determine which addition/deduction attract CPF contribution?

How to determine which addition/deduction attract CPF contribution?

To determine which addition/deduction attracts CPF is to liaise with CPF Board. 
Below is the link for your reference or contact CPF Board for any inquiries:
https://www.cpf.gov.sg/Assets/employers/Documents/Allowances_and_payments_that_attract_CPF_contributions.pdf
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