Short Selling Is Legal on the IDX. Trading Opens 1 October for Just Five Stocks and Two Brokers
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6 min read
Short selling is legal on the Indonesia Stock Exchange (IDX). Yet you have probably never seen anyone do it. That is about to change, but only a little.
On 1 October 2026, the IDX opens short selling for exactly five stocks: ASII, BBCA, BRPT, BUMI and INDF. Only two brokers are allowed to offer it: Ajaib Sekuritas and Semesta Indovest Sekuritas. Bisnis.com, CNBC Indonesia and Katadata all reported the list on 28 and 29 September 2026. This article was written on 30 September 2026, before the first trade.
Here is what short selling is, how it works step by step, and why it is a much riskier tool than buying a stock.
Normally you buy a stock first and sell it later. You hope the price goes up.
Short selling flips the order. You sell first and buy later. You hope the price goes down.
But how can you sell something you do not own? You borrow it. Under the rules, a short sale is a sale of shares the seller does not own at the time of the trade. The shares come from a securities firm through a lending arrangement. You sell them in the market. Later you buy the same number of shares back and return them to the lender.
If the price fell in between, you bought back cheaper than you sold. The gap is your gain. If the price rose, you pay more to buy back than you received. The gap is your loss.
This example is made up, to show the math. It is not a forecast and not a real trade.
Say a stock trades at Rp10.000. One lot on the IDX is 100 shares. You borrow one lot and sell it.
You receive: 100 × Rp10.000 = Rp1.000.000.
Now the price moves. We ignore fees and interest to keep it simple.
| Price when you buy back | Cost to buy back | Your result |
|---|---|---|
| Rp8.000 | Rp800.000 | Gain of Rp200.000 |
| Rp10.000 | Rp1.000.000 | Zero |
| Rp15.000 | Rp1.500.000 | Loss of Rp500.000 |
| Rp30.000 | Rp3.000.000 | Loss of Rp2.000.000 |
Look at the two ends. The most you can ever gain is what you sold for, if the price fell to zero. That would be Rp1.000.000. But a price can rise without any ceiling. So a loss can grow past what you started with.
Investortrust and hukumonline both describe this in the same way: when the price rises, the loss is theoretically unlimited.
Not every stock. The IDX publishes a Short Selling Securities List. It follows Peraturan Bursa Nomor II-H, which sets the rules for margin and short selling.
The first list for October 2026 has five names, all taken from the LQ45 index of Indonesia's most liquid stocks. According to the coverage, they were chosen for their large market value and heavy trading, which makes them harder to push around.
| Ticker | Company |
|---|---|
| ASII | Astra International |
| BBCA | Bank Central Asia |
| BRPT | Barito Pacific |
| BUMI | Bumi Resources |
| INDF | Indofood Sukses Makmur |
Being in the LQ45 was a starting point, not a pass. Not every LQ45 stock made the list. You can look at how some of these stocks have traded on their NetWort pages, such as BBCA, ASII and INDF.
A broker cannot just switch this on. It needs the exchange's permission first.
So far, the IDX has approved two: Ajaib Sekuritas and Semesta Indovest Sekuritas (Katadata, Bisnis.com). Other brokers were still going through approval when the September 2026 restart was reported.
If your broker is not one of the two, you cannot short sell through it yet.
You cannot short sell from a normal stock account. Reports on the rules describe these steps:
Coverage of the OJK rule has also reported a starting fund of Rp50 juta and a track record of at least six months as a share investor (Investortrust). Reports have not agreed on how the Rp50 juta splits between account balance and collateral. Treat it as a rough guide and ask your broker for the exact number.
One rule got looser. Older versions had an uptick rule, which only let you short after the price ticked up. Kontan reported that OJK removed it. A short sell order can now be executed at a price equal to or higher than the last traded price.
The road here was slow. OJK sent a letter on 17 September 2025 that delayed short selling financing. In March 2026, the IDX pushed the restart back again, to 14 September 2026 (Bisnis.com, CNBC Indonesia). Short selling then restarted in phases from 15 September 2026, with the first list due on 28 September.
The exchange has said it wants to watch how the market reacts. That is why the first list is so short.
Losses can grow past your deposit. Your broker can also demand more collateral if the price moves against you. If you cannot pay, the position can be closed by force.
The shares you borrowed also have to be returned on time. If a delivery fails, a buy-in can happen, as our explainer on IDX settlement failures and buy-ins shows. For how forced selling works on borrowed money, see IDX margin trading and forced-sell rules.
Short selling on the IDX starts with five stocks and two brokers. You do not need to do anything about it. But you can see what a short seller would face.
Open the NetWort Market page and look at how liquid the market is today. Check which sectors are moving and how far they swing in a day. That swing is exactly the risk a short seller carries.