The Mandatory Provident Fund (MPF) is Hong Kong's compulsory retirement savings scheme, requiring both employers and employees to contribute 5% of monthly relevant income up to a cap, with those contributions going to private MPF fund managers. The IRS does not recognize the MPF as a qualified pension plan, so employer contributions to your MPF account are generally treated as taxable compensation in the year contributed on your US return. Earnings inside the MPF account, including dividends and capital gains from the MPF's investment funds, are likely subject to current US taxation each year rather than the tax-deferred treatment Hong Kong provides. The MPF's constituent funds may qualify as PFICs if they hold foreign mutual fund-like investments, which would trigger additional annual reporting on Form 8621. Both the MPF account and any related accounts must be reported on FBAR and potentially on Form 8938 if the values cross the applicable thresholds.