Mastering Proration Calculations Step-by-Step for the HK Salesperson Exam

Last updated: April 2026

For candidates preparing for the Estate Agents Authority (EAA) licensing exams, mastering property mathematics is a non-negotiable requirement. Among the most commonly tested mathematical concepts are proration (often referred to in Hong Kong as "apportionment") calculations. These calculations ensure that both the buyer and the seller pay their fair share of property-related expenses during a transaction. For a holistic view of all exam topics, be sure to review our Complete Hong Kong Salesperson Exam Exam Guide.

This mini-article provides a step-by-step guide to understanding, setting up, and solving apportionment questions exactly as they appear on the Hong Kong Salesperson Exam.

What is Proration (Apportionment) in Hong Kong Real Estate?

Proration, or apportionment, is the process of dividing property expenses (outgoings) or income between the vendor (seller) and the purchaser (buyer) based on the exact amount of time each party owns the property. Under standard Hong Kong conveyancing practice, and in alignment with the Conveyancing and Property Ordinance (Cap. 219), financial responsibilities shift on the Completion Date.

If these outgoings are not properly calculated and settled by the vendor, unpaid government charges or management fees can result in registered charges against the property. For more on how unpaid debts affect property titles, read our guide on Easements and Encumbrances.

Common Apportionment Items

In Hong Kong, you will typically be asked to calculate the apportionment for the following items:

Government Rates: Billed quarterly (Jan-Mar, Apr-Jun, Jul-Sep, Oct-Dec).
Government Rent: Also billed quarterly, often on the same demand note as Rates.
Management Fees: Usually billed monthly and paid in advance.
Rental Income: If the property is sold subject to an existing tenancy, rent paid in advance by the tenant must be apportioned so the buyer receives their rightful share.

Typical Apportionment Items & Values (HK$)

The Golden Rules of Proration Calculations

Before touching your calculator, memorize these three golden rules for the EAA exam:

Identify the Completion Date: This is the exact day the property changes hands.
Determine Who "Owns" the Completion Day: In standard Hong Kong exam scenarios, the Purchaser is responsible for outgoings and entitled to income on and from the day of completion. The Vendor is responsible up to the day before completion. (Always read the specific exam prompt to confirm, but this is the default).
Use Exact Calendar Days: Unlike some jurisdictions that use a simplified 360-day year, Hong Kong calculations generally require you to use the exact number of days in the specific month or quarter (e.g., January = 31 days, April = 30 days). Pay attention to leap years if February is involved!

Step-by-Step Proration Formula

To solve any apportionment question, follow this simple three-step framework:

Step 1: Calculate the Total Days in the Billing Period

Determine the exact number of days in the month or quarter in question. For example, the second quarter (April, May, June) has 30 + 31 + 30 = 91 days.

Step 2: Find the Daily Rate

Divide the total bill by the total days in the period.
Formula: Total Bill ÷ Total Days in Period = Daily Rate

Step 3: Allocate the Days and Multiply

Count the number of days the vendor owned the property, and the number of days the purchaser owned it. Multiply the respective days by the Daily Rate.

Practical Exam Scenario: Calculating Quarterly Rates

Let’s walk through a highly realistic Hong Kong Salesperson Exam question.

Scenario: A property transaction is scheduled for completion on May 15th. The Government Rates for the second quarter (April 1st to June 30th) are HK$2,730. The Vendor has already paid the full quarter's rates to the Rating and Valuation Department in advance. How much must the Purchaser reimburse the Vendor upon completion?

Solution:

Step 1: Find the total days in the quarter.
April (30) + May (31) + June (30) = 91 days.
Step 2: Calculate the daily rate.
HK$2,730 ÷ 91 days = HK$30 per day.
Step 3: Determine the Purchaser's days of ownership.
The purchaser takes over on May 15th. They are responsible for May 15th to May 31st (17 days) plus all of June (30 days).
17 + 30 = 47 days.
Step 4: Calculate the reimbursement amount.
47 days × HK$30/day = HK$1,410.

Answer: The Purchaser must reimburse the Vendor HK$1,410 as part of the completion statement.

Handling Rental Income Apportionment

When a property is sold subject to a tenancy, the calculation logic is identical, but the flow of money reverses. Because rent is typically paid by the tenant to the landlord (vendor) in advance on the first of the month, the Vendor must refund the Purchaser for the days the Purchaser owns the property.

Example: Rent is HK$15,000 per month, due on the 1st. Completion is on November 21st. November has 30 days.

Daily Rent: HK$15,000 ÷ 30 = HK$500/day.
Purchaser's Days: November 21st to 30th = 10 days.
Vendor owes Purchaser: 10 days × HK$500 = HK$5,000.

Professional Ethics and Proration

While solicitors ultimately draft the formal Completion Statement (apportionment account), estate agents must be competent enough to explain these estimated costs to their clients beforehand. Failing to inform a buyer about the thousands of dollars they may need to reimburse the seller for prepaid rates and management fees can lead to transaction disputes.

Providing accurate, transparent financial estimates is a core component of the EAA's Code of Ethics. For more on maintaining professional conduct, review our guide on Real Estate Ethics and Standards.

Frequently Asked Questions (FAQs)

Do I use a 365-day year or a 360-day year for the HK Salesperson Exam?

Unless the exam question specifically instructs you to use a 30-day month or a 360-day year, you must use exact calendar days for Hong Kong apportionment calculations. Always verify the exact number of days in the specific month or quarter mentioned in the prompt.

Who is responsible for the property outgoings on the actual day of completion?

Under standard Hong Kong conveyancing practice, the Purchaser is responsible for outgoings (and entitled to rental income) on and from the day of completion. The Vendor's responsibility ends the day before completion.

Are utility deposits (water, gas, electricity) prorated during completion?

Generally, no. Standard practice in Hong Kong is for the Vendor to close their utility accounts and receive their deposit refunds directly from the utility companies. The Purchaser will open new accounts and pay new deposits. However, parties can occasionally agree to transfer the deposits for a flat reimbursement sum, but this is not typically tested as a proration calculation.

What happens if the vendor hasn't paid the quarterly rates before completion?

If the Vendor has not paid an outgoing that spans the completion date, the Purchaser's solicitor will typically withhold the Vendor's portion of that outgoing from the balance of the purchase price. The solicitor will then use those funds, combined with the Purchaser's portion, to settle the outstanding bill with the government or management office.

Why is it important for an estate agent to understand these calculations if solicitors handle the completion statement?

According to EAA guidelines, estate agents must provide clients with a reasonably accurate estimate of the funds required for completion. If an agent fails to advise a purchaser that they need extra cash to reimburse the vendor for prepaid quarterly rates and management fees, the purchaser may face a cash shortfall on completion day, potentially jeopardizing the transaction.