Should you choose a prepaid SIM or a monthly plan?
If your usage is steady and you consume the full allowance most months, a monthly plan is usually cheaper per GB. If your usage swings, or you only need a large allowance in particular months, a prepaid card is more flexible — no contract term and no administration fee. The other limit on prepaid is capability: most prepaid cards carry data and calls only, without dual-number service, a mainland number issued after real-name verification, or anything that requires a postpaid account. The prepaid page on Telecom Rex 電訊暴龍 lists prepaid products only; monthly plans are listed separately on the comparison page, so the two are never mixed in one table.
How is Greater Bay Area and mainland data counted?
Mainland data on a Hong Kong prepaid card works one of two ways: local and mainland usage share a single allowance, or the mainland allowance is separate. With a shared allowance, mainland data stops when the local allowance runs out; with a separate one, it keeps working. Coverage wording matters too — "Greater Bay Area" generally means the nine Guangdong cities plus Macau, which is not the same as all of mainland China. Travel beyond the Greater Bay Area on a GBA-only allowance and the card falls back to roaming rates. The coverage column on this page states which type each card is; check it before buying.
How does prepaid SIM expiry work?
A prepaid card carries two separate clocks: the validity of the data pack, and the validity of the stored value itself. The data pack runs from the activation date, commonly anywhere from 30 to 365 days, and unused data is not carried over once it lapses. Stored-value validity runs from your last top-up, and topping up before the deadline extends the balance. The two are counted independently, so an expired data pack does not mean the stored value is gone. Check both dates before buying — it matters most for a low-usage card bought for an older relative or as a backup phone. Prices on this page come from published product information and are shown with the date they were recorded.
