You borrow shares you don’t own, sell them for cash, and hope the price drops so you can buy them back cheaper and pocket the difference. That is short selling in a sentence. For a New Zealand investor, the strategy sounds straightforward on paper, but the financial mechanics shift quickly once money is in motion. The difference between a winning trade and a margin call comes down to costs, timing, and one number that catches most people out: the price can keep rising, and your losses keep growing with it.
Disclosure: Some links on this page are affiliate links. If you make a purchase through them, Britwealth may earn a commission at no extra cost to you. We only include products and services that are relevant to the topic.
This article is general information only and does not constitute professional advice. For your specific situation, consult a qualified professional.
Short selling is legal in New Zealand and regulated like any other trade. The NZX, the country’s main stock exchange, allows it under standard market rules. But not every stock can be shorted, and not every broker offers the service. If you are new to the idea, start with the basics of how the market works before borrowing shares you may need to replace at a much higher price. Here is what you actually need to know.
Short selling is the practice of borrowing shares you do not own, selling them at the current market price, and later buying them back — ideally at a lower price — to return to the lender. The difference, minus costs, is your profit or loss.
What I tend to notice is how many people focus on the potential profit and skip past the mechanics of what happens when the trade goes the other way. The costs matter, but the structure of the risk matters more.
What a Short Trade Actually Costs — Fees, Interest, and the Unlimited Loss That Changes Everything
Short selling has three cost layers that do not exist when you buy shares. Borrow fees cover the cost of borrowing the shares from the lender. Margin interest applies to the money you borrowed through your margin account to fund the trade. And if the stock pays a dividend while you are short, you pay that dividend to the lender — out of your own pocket.
The table below shows the cost comparison between a standard buy trade and a short sell trade for the same stock.
→ Scroll right to see all columns
| Cost Type | Buying Shares (Long) | Short Selling |
|---|---|---|
| Maximum loss | Capped at purchase price | Unlimited |
| Borrow fee | None | Paid while position is open |
| Margin interest | Only if using margin | Almost always applies |
| Dividend treatment | You receive dividends | You pay dividends to lender |
| Broker commission | Entry + exit | Entry + exit |
The net profit formula for a short trade is: (sell price − buyback price) × number of shares − borrow fees − commissions − spreads − dividends owed. In practice, a stock that falls only 5% may produce no profit at all once the costs are deducted. A stock that rises 5% can produce a loss far larger than the original margin deposit.
Where Short Sellers in New Zealand Get It Wrong
Underestimating borrow fees on hard-to-short stocks
Brokers classify stocks as easy-to-borrow or hard-to-borrow. Hard-to-borrow stocks carry higher fees because fewer shares are available from lenders. A fee that looks small on a daily basis — say 0.5% annualised — can eat a meaningful share of the profit if the trade stays open for weeks or months. The fee is charged every day the position is open, not just at entry.
Ignoring the short squeeze trigger
A short squeeze happens when a stock rallies sharply and short sellers rush to buy back shares to limit losses. That buying pressure pushes the price higher, which forces more short sellers to cover. The research notes that a stock can rise on “bad” news if the market expected worse or if traders were already positioned for the drop. Checking upcoming earnings dates and regulatory decisions before entering a short trade is part of the work.
Forgetting dividend obligations
If the stock you have shorted goes ex-dividend while your position is open, you owe that dividend to the person who lent you the shares. The payment comes out of your account on the dividend date. For a stock with a 3% dividend yield held short for several months, that cost alone can erase a modest gain.
Assuming all NZ stocks are available to short
Not every stock on the NZX can be shorted. Brokers restrict certain stocks based on lender availability, liquidity, and internal risk policies. Before planning a trade, check whether the stock is on your broker’s short list. Even then, the broker may recall the shares if the lender demands them back, forcing you to close the position earlier than planned.
How to Structure a Short Trade in Practice — From Setup to Exit
Opening a margin account with a suitable broker
Short selling requires a margin account, not a standard cash account. You need to apply for margin approval with a broker that offers short selling services to New Zealand residents. The account must hold minimum equity — the exact amount varies by broker. Once approved, you can place a sell short order, but the broker must first locate shares to borrow. If the broker cannot locate shares, the order cannot be filled.
Researching the stock before you short
Look for companies with weak fundamentals, declining revenue, or overvalued market positions relative to peers. The argument is that you are betting on a business problem, not just a chart pattern. Examine financial statements, read analyst reports, and check whether the stock is easy or hard to borrow. A stock that is already heavily shorted by other traders carries a higher squeeze risk.
Placing the trade and setting exit rules
Enter a sell short order through your broker at the current market price or a limit price. Set a stop-loss order that buys the shares back if the price rises above a level you decide in advance. The stop-loss is your only protection against unlimited loss, and it must be set at a price where you can afford to be wrong. Also set a profit target — a price at which you buy back the shares and close the trade. Without both exit rules, the trade is open-ended.
Emerging trends in NZ short selling
New Zealand’s market is smaller than Australia or the US, which means liquidity is lower and short squeezes can be more violent when they happen. There is also growing regulatory attention on naked short selling — selling shares without first borrowing them — which is illegal in most markets, including New Zealand. If you are shorting NZ stocks, you must work through a broker who confirms locate-and-borrow before each trade. That rule is not optional.
Frequently Asked Questions About Short Selling in New Zealand
Can I short any stock on the NZX? ▾
How long can I hold a short position? ▾
What happens if the stock I shorted pays a dividend? ▾
Is short selling legal in New Zealand? ▾
What is the minimum amount I need to start short selling? ▾
Can my broker close my short position without asking me? ▾
Short Selling Is a Tool, Not a Shortcut — Know What You Are Borrowing
The argument for short selling is that it improves market efficiency and lets investors profit from overvalued stocks. The argument against it is that it amplifies losses and can destabilise prices in a downturn. Both are true. What matters for a New Zealand investor is the practical reality: short selling is a structured financial strategy that requires a margin account, ongoing cost management, and a clear exit plan before the trade is entered. The unlimited loss feature is not a hypothetical risk — it is the defining mechanic of the trade.
Remember: this article is general information only. For advice on your specific situation, speak to a qualified professional.
If this was useful, you might also want to read Essential Investment Tips for New Zealand Beginners.
Sources and Further Reading
Beyond KiwiSaver: Alternative Investment Options for New Zealanders — A broader look at investment strategies available alongside standard retirement accounts.
Moneysavers (2024). The Art of Short Selling: A New Zealand Perspective. 🔗
Spocket (2024). Short Selling Guide. 🔗
