A good place to grow.

IB City is BACC’s optional study companion. These reward rules apply from September 11, 2026.

Three kinds of progress

XP records study participation and unlocks city levels. It is not an IB grade or school credit. City Coins buy virtual buildings and upgrades; they have no cash value. HKD checkout credit is a discount on your own eligible BACC subscription checkout, not withdrawable cash. These three balances cannot be exchanged with each other, transferred, sold, or used to buy academic results.

Study and construction

Every new city receives 250 coins. Save a study session with every question attempted to earn 80 XP and 60 coins once per UTC calendar day. Your first saved diagnostic also earns 40 XP and 40 coins once. Free and Premium students receive the same daily reward. Building costs are shown before construction; each landmark has three tiers. Your city never loses buildings because you miss a day. Optional CAS-themed activities do not certify school CAS requirements.

Campus missions

Short campus missions have three decisions with explanations. Get at least two right to earn 30 XP and 40 City Coins once per UTC day, across all missions. Replay for practice after collecting the daily bonus. Signed-in answers and rewards are checked and saved on the server. Guest missions use sample rewards that do not transfer into a saved city. Missions never award HKD credit and do not replace IB assessment. The current mission scenarios alternate between two sets each day. Move your buildings to empty plots for free; their tiers and your coin balance stay the same.

Successful referrals

Your friend must follow your referral link before creating a new BACC account. The referral cookie lasts 30 days; the most recently followed valid invitation is used. Existing accounts cannot be referred. Their first subscription payment must take place within 30 days of account creation, with at least HK$50 paid by card, or its USD equivalent at the promotional conversion below. Signups, free trials, renewals, and advisory purchases do not earn referral rewards.

After a 14-day payment hold and a fresh payment check, you receive HK$50 checkout credit and 500 City Coins. Your friend receives the standard welcome gift; they do not receive a second HK$50 bonus. A genuine parent-funded subscription can qualify. Self-referrals, funding your own referred account, fabricated accounts, and attempts to manipulate rewards are ineligible.

Using HKD credit

You can apply available credit to the first payment of your own new monthly or annual subscription. Existing active subscriptions, automatic renewals, parent sponsorship checkouts, and advisory purchases are excluded. Credit remains available for a future eligible checkout and does not expire under these rules. At least one unit of the checkout currency remains payable by card. Stripe displays the discount and renewal price before payment.

HKD checkout applies HKD credit directly. For existing USD plans, BACC uses a fixed promotional conversion of HK$7.80 per US$1, not a live exchange rate. The discount is rounded down to USD cents; the corresponding HKD debit is rounded up to HKD cents. Review the quote before proceeding. Any applicable taxes are calculated at checkout. Credit is reserved when checkout opens and restored after the one-hour session expires if unpaid. Leaving checkout does not immediately release its reservation.

Refunds and adjustments

The site’s existing 30-day subscription refund offer remains applicable. Any partial or full refund, or a payment dispute on the qualifying referral payment, cancels its entire referral reward, including rewards already released after day 14. Reversals subtract HK$50 and 500 City Coins once. Already-spent rewards can leave an adjusted negative balance; future rewards first offset it. No automatic card charge is made to recover rewards. Refunded purchases do not turn promotional credit into a cash refund; contact support about restoring the promotional portion of your own refunded purchase.

Privacy and help

Your city is private to your account. Invitees’ names, email addresses, grades, and payment details are not shown to referrers. Only referral status and eligible release timing are displayed. Sharing a link does not send a message automatically. For reward or payment reconciliation, contact [email protected].

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