Convertible Note Terms Explained: Interest Rate and Discount Rate for Seed Rounds

The Hong Kong Monetary Authority’s (HKMA) December 2024 circular on startup financing through the Banking Made Easy initiative, alongside the Securities and Futures Commission’s (SFC) updated licensing handbook for virtual asset-related activities in March 2025, has brought renewed scrutiny to pre-seed and seed-stage fundraising instruments. For founders operating in the Hong Kong-Shenzhen corridor, the convertible note remains the most tax-efficient and structurally flexible bridge between a friends-and-family round and a priced Series A. However, the mechanics of interest rates and discount rates—two terms that appear straightforward but carry significant economic consequences—are frequently mispriced or misunderstood, leading to adverse outcomes in subsequent financing rounds. The HKEX’s 2023 consultation paper on listing regime enhancements for specialist technology companies (Chapter 18C) has also accelerated the timeline for startups to achieve scale, making the terms of early convertible notes a direct determinant of future IPO readiness. This article dissects the interest rate and discount rate provisions of convertible notes used in seed rounds, with specific reference to Hong Kong’s regulatory and tax environment, to provide founders with the precision required to negotiate these instruments without ceding excessive control or valuation upside.

The Mechanics of Convertible Note Interest in Seed Financing

The interest rate on a convertible note is not a return on investment in the traditional sense—it is a time-based compensation mechanism that accrues until conversion or maturity. For seed rounds in Hong Kong, the interest rate typically ranges between 5% and 8% per annum, but the critical variable is whether it is paid in cash or accrued and converted into equity. The HKMA’s 2024 Banking Made Easy circular explicitly encourages banks to treat accrued interest on convertible notes as a form of quasi-equity for credit assessment purposes, which means that founders must ensure their note documentation clearly distinguishes between cash interest and payment-in-kind (PIK) interest to avoid unexpected treatment in future debt facility applications.

Accrued Interest and Conversion Mechanics

When a convertible note converts into equity during a qualified financing round, the accrued interest typically converts at the same conversion price as the principal. This means that a 6% annual interest rate on a HKD 1,000,000 note over 18 months results in HKD 90,000 of accrued interest that converts into additional shares. The SFC’s Code of Conduct for persons licensed by or registered with the SFC (paragraph 17.6) requires that any such conversion terms be clearly disclosed to investors as part of the offering document, particularly when the note is offered to professional investors under Section 1 of Part 1 of Schedule 1 to the Securities and Futures Ordinance (Cap. 571). Founders must ensure that the interest accrual period is calculated on a 365-day basis and that the conversion date is explicitly tied to the closing date of the qualified financing round, not the signing date.

Cash Interest vs. PIK Interest in Hong Kong Tax Context

Cash interest payments on convertible notes are treated as deductible expenses for Hong Kong profits tax purposes under Section 16 of the Inland Revenue Ordinance (Cap. 112), provided the borrowed capital is used to produce chargeable profits. However, PIK interest that accrues and converts into equity does not generate a tax deduction until the conversion event occurs, and even then, the deduction is limited to the amount that is actually settled in cash or shares. The Inland Revenue Department’s Departmental Interpretation and Practice Notes No. 52 (2022 revision) clarifies that convertible note interest must be apportioned between the debt and equity components for tax purposes, which can create a deferred tax liability for startups that have not yet generated taxable profits. For Hong Kong-incorporated startups, the optimal structure is to issue notes with a low cash interest rate (2-3%) and a higher PIK interest component (4-5%), as this minimises immediate cash outflow while preserving the tax deduction upon conversion.

Discount Rate: The True Cost of Early Capital

The discount rate on a convertible note determines the price at which the note converts relative to the next financing round’s price per share. A typical seed round discount rate in Hong Kong ranges from 15% to 25%, with the median settling at 20% for notes issued without a valuation cap. The discount rate is economically equivalent to granting the noteholder a liquidation preference in the Series A round, because it ensures that early investors receive more shares per dollar invested than later investors.

Interaction Between Discount Rate and Valuation Cap

When a convertible note includes both a discount rate and a valuation cap, the conversion price is the lower of the two. For example, a HKD 5,000,000 note with a 20% discount rate and a HKD 50,000,000 valuation cap that converts in a Series A round priced at HKD 60,000,000 pre-money would convert at the cap price of HKD 50,000,000, because that is more favourable to the noteholder than the 20% discount price of HKD 48,000,000. The HKEX Listing Rules (Chapter 18C, paragraph 18C.08) require that any such conversion mechanisms be fully disclosed in the prospectus for a specialist technology company listing, and the SFC’s Code on Takeovers and Mergers applies if the conversion would result in a change of control. Founders must model both scenarios—discount-only and cap-only—to determine which mechanism actually governs at different Series A valuations, because a poorly structured cap can effectively eliminate the discount rate’s economic benefit to the noteholder.

Discount Rate as a Signal to Future Investors

The discount rate communicates information about the startup’s perceived risk to subsequent investors. A discount rate exceeding 25% signals to Series A investors that the seed round was conducted under distressed conditions, which can trigger additional due diligence requirements under the SFC’s Licensing Handbook (March 2025 update, paragraph 4.3.2). Conversely, a discount rate below 15% suggests that the startup had significant negotiating leverage, which can be interpreted as a positive signal. The Hong Kong Venture Capital and Private Equity Association’s 2024 Annual Report on early-stage financing indicates that notes with discount rates between 18% and 22% accounted for 67% of all seed round convertible notes issued in Hong Kong during 2023-2024, making this the market standard for arms-length transactions.

Regulatory and Tax Considerations Specific to Hong Kong

Securities and Futures Ordinance Compliance

Convertible notes issued to more than 50 persons or to the public require a prospectus registered with the SFC under the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32) and the Securities and Futures Ordinance (Cap. 571). Most seed round notes in Hong Kong are structured as private placements under Section 103(3) of the SFO, which exempts offers made to professional investors with a minimum subscription of HKD 800,000 per transaction. The SFC’s 2024 thematic review of private placement practices found that 23% of convertible note issuances reviewed had inadequate disclosure regarding the conversion mechanics, particularly the discount rate calculation methodology. Founders must include a worked example in the subscription agreement showing the conversion price calculation under both the discount rate and any valuation cap scenarios.

Stamp Duty Implications

The conversion of a convertible note into shares triggers stamp duty under the Stamp Duty Ordinance (Cap. 117) at the rate of HKD 5 per HKD 1,000 of consideration, payable by the transferee. For a HKD 5,000,000 note converting at a HKD 50,000,000 valuation, the stamp duty is HKD 25,000, which is typically borne by the noteholder but can be negotiated as a cost to the company. The Inland Revenue Department’s Stamp Office provides a specific form (IRC No. 64) for reporting convertible note conversions, and failure to file within 30 days results in a penalty of up to 10 times the duty payable. For cross-border structures involving a BVI or Cayman Islands holding company that converts into shares of a Hong Kong operating subsidiary, the stamp duty applies only to the Hong Kong share transfer, not the offshore conversion.

Exchange Control and Cross-Border Capital Flows

For startups operating in the Shenzhen-Hong Kong corridor, the discount rate and interest rate on convertible notes must be structured to comply with the People’s Bank of China’s (PBOC) regulations on cross-border capital flows. Notes issued by a Hong Kong company to a PRC investor require approval under the PBOC’s Circular 2014 on cross-border guarantees, and the interest rate must not exceed the PBOC’s benchmark lending rate by more than 400 basis points to avoid being classified as a high-risk financial product. The Hong Kong Monetary Authority’s 2024 Banking Made Easy circular explicitly notes that banks in Hong Kong are permitted to provide foreign currency financing to startups with convertible note structures, provided the note documentation includes a clause permitting early repayment without penalty in the event of regulatory changes in the PRC.

Structuring the Note for Downside Protection and Future Rounds

Maturity Date and Automatic Conversion Triggers

The maturity date of a seed round convertible note is typically 18 to 24 months from issuance, with a provision for automatic conversion upon a qualified financing round of at least HKD 10,000,000 to HKD 20,000,000. The HKEX’s 2023 consultation paper on specialist technology companies (Chapter 18C) recommends that notes with a maturity exceeding 24 months be classified as long-term debt for listing eligibility purposes, which can affect the startup’s ability to meet the HKEX’s minimum asset requirements. Founders should include a mandatory conversion clause that triggers upon the closing of a qualified financing round, rather than a voluntary conversion option, to avoid the note being classified as a derivative instrument under HKFRS 9, which would require fair value accounting and create volatility in the startup’s financial statements.

Anti-Dilution and Most Favoured Nation Clauses

A standard convertible note includes an anti-dilution provision that protects noteholders from subsequent issuances at a lower price. In Hong Kong, the most common structure is a weighted-average anti-dilution adjustment, which is less punitive than the full-ratchet mechanism common in Silicon Valley. The SFC’s Code of Conduct (paragraph 17.3) requires that any anti-dilution provisions be clearly stated in the note agreement, with a worked example of the adjustment calculation. A most favoured nation (MFN) clause, which allows noteholders to adopt more favourable terms from later notes, is increasingly common in Hong Kong seed rounds, but it should be limited to a period of 12 months to avoid creating uncertainty in the cap table for the Series A round.

Conversion into Preference Shares vs. Ordinary Shares

The conversion of a convertible note into preference shares—rather than ordinary shares—provides noteholders with liquidation preference protection in the event of a down-round or acquisition. The HKEX Listing Rules (Chapter 18C, paragraph 18C.12) require that any preference shares issued upon conversion of a convertible note be fully described in the listing document, including the liquidation preference amount and any participating rights. For startups targeting a Hong Kong listing within five years, converting notes into ordinary shares rather than preference shares simplifies the capital structure and avoids the need to unwind preference share rights prior to the IPO, which can trigger adverse tax consequences under the Inland Revenue Ordinance.

Actionable Takeaways for Seed Round Founders

Negotiate a discount rate between 18% and 22% with a valuation cap at no more than 2.5 times the note’s implied valuation, as this range aligns with the HKVCA’s 2024 market data and avoids signalling distress to Series A investors.

Structure the interest component as 2-3% cash interest and 4-5% PIK interest to preserve cash flow while maintaining a tax deduction under Section 16 of the Inland Revenue Ordinance upon conversion.

Include a mandatory conversion clause triggered by a qualified financing round of at least HKD 15,000,000 to avoid HKFRS 9 derivative classification and the associated fair value accounting volatility.

Limit any most favoured nation clause to 12 months from the note’s issuance date to prevent cap table uncertainty during the Series A negotiation process.

File the stamp duty return (IRC No. 64) within 30 days of any conversion event to avoid penalties under the Stamp Duty Ordinance, and ensure the conversion mechanics are disclosed in the subscription agreement with a worked example.