How Does the Hong Kong Dollar Peg to the US Dollar Actually Work?
Direct answer
The HKD peg in brief
The Hong Kong dollar is held between HK$7.75 and HK$7.85 per US dollar by a currency board. The Hong Kong Monetary Authority's Convertibility Undertakings commit it to sell HK dollars to banks at 7.75 (the strong side) and buy them at 7.85 (the weak side), and the monetary base is fully backed by US dollar assets in the Exchange Fund. When the rate hits 7.85, the HKMA buys HK dollars, which shrinks interbank liquidity and pushes Hong Kong interest rates up until outflows stop; at 7.75 it does the reverse. On June 26, 2025 the weak side was triggered and the HKMA bought HK$9.42 billion. The system has run since October 17, 1983, with the current symmetric band since May 2005.
- Band: HK$7.75–7.85 per US$ (HKMA)
- Monetary base fully backed by US dollar assets
- Strong side 7.75: HKMA sells HKD
- weak side 7.85: HKMA buys HKD
- Weak side triggered June 26, 2025: HK$9.42bn bought
- Rate gaps with the US decide which edge it drifts to
USD/HKD is the flattest major chart you will ever see: a decade of trading inside a band 1.3% wide. That is by design, and the mechanism explains when it drifts to the edges.
What people on X are asking
In May 2025 a large market account asked: "Is the US Dollar/Hong Kong Dollar peg about to break?". In June 2025 a thread asked why the HKD was "hitting the weak end of its peg" even while the dollar was weak elsewhere, and answered that it was "all about interest rates". Another post reported that Hong Kong's de facto central bank "sold 1.2 billion U.S. dollars" as the currency hit the weak end. Here is how the system works and what the data show.
What people in the thread said
- @JaeKim1089208 noted the rate had traded between 7.75 and 7.85 for years. Correct: that has been the band since May 2005.
- @CntrprtyRsk observed that the pressure was on the strong side, which peg doomsayers had not expected. Also correct: the HKMA said the strong side was triggered several times in early May 2025.
- @InvestiBrew argued China's rate cuts meant it would buy US bonds to keep the peg. That mixes up two systems: the peg is run by the HKMA's currency board, not the People's Bank of China.
These are community comments, summarised in our words; the data and sources below come first.
The fact-checked answer
The rules. The HKMA describes the Linked Exchange Rate System as a currency board: the monetary base is "fully backed by US dollar assets", and every change in the monetary base is matched by a change in US dollar assets held in the Exchange Fund at a fixed rate. Under the Convertibility Undertakings, the HKMA "commits to sell Hong Kong dollars upon request by banks at the strong-side CU of HK$7.75 per US dollar, and to buy Hong Kong dollars upon request by banks at the weak-side CU of HK$7.85". The system dates from October 17, 1983; in May 2005 the HKMA added the strong-side undertaking at 7.75 and moved the weak side from 7.80 to 7.85, making the band symmetric around 7.80.
The adjustment is through interest rates. When money leaves and the rate reaches 7.85, banks sell HK dollars to the HKMA for US dollars. The HK dollars are removed from the banking system (the Aggregate Balance falls), interbank rates rise, and holding HK dollars becomes more attractive again. Inflows at 7.75 work in reverse. The HKMA calls this an "automatic interest rate adjustment mechanism". It does not need to forecast or choose a rate.
The June 2025 example. The HKMA said the weak-side undertaking was triggered during New York hours on June 26, 2025, and it sold US dollars for HK$9.42 billion on banks' request (about US$1.2 billion at 7.85), reducing the Aggregate Balance to HK$164.1 billion. It noted the weak side was last triggered in May 2023, and that the strong side had been triggered several times in early May 2025: both edges in a few weeks.
UXS chart
USD/HKD since the 2005 band (HK$ per US$)
HK dollars per US dollar: latest
7.8402
November 6, 2026
Highest in chart period
7.8499
April 12, 2018
Lowest in chart period
7.7493
November 2, 2012
Change over 1 year
+0.8%
vs November 6, 2025
Year by year: HK dollars per US dollar
Computed by UXS from the same data as the chart. Tap a column header to sort. * = year to date (latest data November 6, 2026).
| 2026* | 7.8402 | +0.7% | 7.8486 | 7.7844 |
| 2025 | 7.7833 | +0.2% | 7.8499 | 7.7500 |
| 2024 | 7.7677 | -0.6% | 7.8368 | 7.7617 |
| 2023 | 7.8109 | +0.1% | 7.8499 | 7.7920 |
| 2022 | 7.8015 | +0.0% | 7.8499 | 7.7693 |
| 2021 | 7.7996 | +0.6% | 7.8034 | 7.7515 |
| 2020 | 7.7534 | -0.5% | 7.7951 | 7.7498 |
| 2019 | 7.7894 | -0.5% | 7.8499 | 7.7850 |
| 2018 | 7.8305 | +0.2% | 7.8499 | 7.8043 |
| 2017 | 7.8128 | +0.8% | 7.8267 | 7.7540 |
| 2016 | 7.7534 | +0.0% | 7.8270 | 7.7505 |
| 2015 | 7.7507 | -0.0% | 7.7686 | 7.7495 |
Which edge, and why. On FRED's daily data, USD/HKD has stayed between 7.7493 and 7.8499 since June 2005. Counting days at or beyond each edge:
Days at the edges of the band (FRED daily noon rates)
Computed by UXS from FRED DEXHKUS. Noon New York readings can differ slightly from Hong Kong market rates. Tap a column header to sort.
| 2015 | 7.7495 | 7.7686 | 0 | 104 |
| 2018 | 7.8043 | 7.8499 | 53 | 0 |
| 2019 | 7.7850 | 7.8499 | 35 | 0 |
| 2020 | 7.7498 | 7.7951 | 0 | 122 |
| 2022 | 7.7693 | 7.8499 | 91 | 0 |
| 2023 | 7.7920 | 7.8499 | 46 | 0 |
| 2025 | 7.7500 | 7.8499 | 42 | 3 |
| 2026 to Nov 6 | 7.7844 | 7.8486 | 0 | 0 |
The weak-edge years (2018–19, 2022–23) were years of rising or high US rates: when US dollar rates are well above Hong Kong rates, carry traders borrow HK dollars and buy US dollars, pushing the rate to 7.85 until the HKMA's purchases tighten liquidity. In 2020, after the Fed cut rates close to zero, it sat at the strong edge instead.
Can it break? A currency board fails only if the authority runs out of foreign assets to honour the undertakings or chooses to change the system. Because the monetary base is fully backed by US dollar assets, the HKMA can absorb outflows; the cost is borne through higher local interest rates. Speculating on a break has been a losing trade for decades, but a peg is a policy, not a law of nature.
Mainland China uses a different system, a managed float around a daily reference rate; see how China's daily yuan fixing works.
Decision helper
| If USD/HKD is… | What usually happens |
|---|---|
| At 7.85 | HKMA buys HKD; HK rates rise; liquidity tightens |
| At 7.75 | HKMA sells HKD; HK rates fall; liquidity loosens |
| In the middle | No intervention; rates and flows decide the drift |
| US rates far above HK rates | Drift toward 7.85 |
For how rate gaps move other currencies, see does a rate hike always make a currency stronger and what a carry trade is; and for a managed currency of a different kind, is the Swiss franc still a safe haven.
Common mistakes
- Reading a move to 7.85 as a sign the peg is breaking.
- Forgetting that the defence works through interest rates.
- Assuming the HKMA targets 7.80 inside the band.
- Trading USD/HKD with leverage for tiny moves and ignoring costs.
FAQ
What is the Hong Kong dollar peg?
A currency board that keeps HK$7.75–7.85 per US dollar.
Who maintains it?
The Hong Kong Monetary Authority, through its Convertibility Undertakings.
What happens at 7.85?
The HKMA buys HK dollars from banks, draining liquidity and pushing local rates up.
When was the weak side last triggered?
On June 26, 2025, when the HKMA bought HK$9.42 billion, per its statement that day.
Since when has the peg existed?
Since October 17, 1983; the 7.75–7.85 band since May 2005.
Why does the HKD move to the weak side?
Usually because US interest rates are well above Hong Kong rates, encouraging outflows.
Sources
- HKMA: Linked Exchange Rate System
- HKMA: How does the LERS work
- HKMA: Milestones of monetary reform
- HKMA: Response to media enquiries, June 26, 2025
- FRED: Hong Kong dollars to US dollar (DEXHKUS)
Facts checked November 10, 2026. X posts are cited as evidence of the question, not of the answer.