Fare subsidy calculator

The Public Transport Fare Subsidy Scheme (PTFSS), as the Government states it: one-third of the month's public transport expenses above $500, capped at $400 a month for each Octopus account and each AlipayHK account. The two accounts are computed separately and never added together.

Fares · Subsidy · Trip log · Data and sources

Spent with Octopus this month (HKD) Spent with AlipayHK this month (HKD) Compute the subsidy

The rule, quoted from the Government's page

one-third of their actual monthly public transport expenses in excess of a monthly threshold, subject to a maximum of $400 per month for each Octopus and each AlipayHK account. Public transport expenses recorded separately under the AlipayHK account and Octopus cannot be combined for the calculation of subsidies. From 1 June 2025 onwards, the monthly threshold under the Scheme has been raised from $400 to $500, while the subsidy rate and the monthly subsidy cap remain unchanged.

Also on that page: 33.33% is adopted for calculating the monthly subsidy. $400 is the subsidy cap.

The Government publishes no rounding rule: the page states the rate (one-third) and the $400 monthly cap, but not how the amount is rounded to dollars. This service therefore returns both figures instead of choosing silently - "subsidy_hkd" is the whole-dollar amount truncated downwards (never rounded up) and "subsidy_exact_hkd" is the same computation kept to two decimals. The truncated figure is never the optimistic one, which is the safe direction for a number a reader might act on.

• PTFSS - Purpose and Features ($500 threshold, one-third, $400 cap, separate accounts)
• PTFSS - Subsidy Calculation (worked examples, the 33.33% remark, the $400 cap)
• PTFSS - subsidy calculation page, Chinese version (read to cross-check the same statements)