https://www.iras.gov.sg/taxes/individual-income-tax/basics-of-individual-income-tax/tax-reliefs-rebates-and-deductions/tax-reliefs/central-provident-fund-(cpf)-cash-top-up-relief

配偶在2024年的收入不超过$8,000，你今年（2025年）用现金给他填补（MA或者SA），满足条件的情况下，在2026年报税（YA2026）的时候，可以有最多$8,000的减税额。　

配偶的收入，包含应纳税收入，免税收入，以及海外收入。

Dependant must not have an annual income** of more than $8,000 in the year 2023 (i.e. the year preceding the year in which the top-up was made in 2024).

** Annual income includes:　

Taxable income (e.g. trade, employment and rental)　

Tax-exempt income (e.g. bank interest, dividends and pension)　

Foreign-sourced income regardless of whether it has been remitted to Singapore