What are ARA and ARB on Indonesian stocks?
ARA and ARB are the Indonesia Stock Exchange's daily price limits for a stock. ARA (Auto Rejection Atas) is the highest price a stock may trade at on a given day, and ARB (Auto Rejection Bawah) is the lowest. Any order priced beyond either boundary is automatically rejected by the exchange — hence "auto rejection". These are IDX rules that apply to every broker in Indonesia, not Pluang settings, and they exist to slow down extreme single-day price swings. They also matter directly on Pluang, because a market order's buy estimate is calculated from the day's ARA price, which is why that estimate reads higher than the live price.
Current limits, per IDX rules effective 8 April 2025:
| Price reference | ARA (upper limit) | ARB (lower limit) |
|---|---|---|
| Rp50 – Rp200 | 35% | 15% |
| Rp200 – Rp5,000 | 25% | 15% |
| Above Rp5,000 | 20% | 15% |
Note that ARB is a flat 15% across every price band, while ARA varies by band. Older tables showing tiered ARB percentages predate the April 2025 revision and are no longer accurate.
How the limits are applied. Each morning the exchange sets the boundaries as a percentage above and below the stock's reference price for that day. A stock trading at Rp3,000 in the Rp200–5,000 band, for example, may rise at most 25% to Rp3,750 and fall at most 15% to Rp2,550 during that session.
What ARA and ARB mean for your order on Pluang:
- An order priced outside the band is rejected by the exchange, not by Pluang — no fee is charged and nothing is deducted.
- When a stock is sitting at its ARA or ARB, matching can stall entirely, because no one is able to trade past the boundary. An open order may sit unmatched even though it is priced validly.
- A market order cannot escape the limits either: it takes the best available price, but that price can never be outside the day's band.
- On a market order buy estimate, the day's ARA sets the worst-case boundary — which is why a buy estimate reads higher than the live price.
A stock hitting ARA or ARB is not a Pluang event. It is an exchange-wide condition affecting every investor in that stock at that moment, regardless of which broker they use.
Related questions:
Q: What do the abbreviations ARA and ARB stand for?
They are Indonesian terms. ARA is Auto Rejection Atas, meaning auto-rejection above — the daily ceiling. ARB is Auto Rejection Bawah, meaning auto-rejection below — the daily floor. "Atas" and "bawah" simply mean upper and lower, so the pair describes the two ends of the price range a stock is allowed to move within on a single trading day.
Q: Are ARA and ARB set by Pluang?
No. Both are set by the Indonesia Stock Exchange and apply identically across every Indonesian broker. Pluang cannot widen, narrow or waive them for your account. The current structure — a 15% flat ARB and a tiered ARA of 20% to 35% depending on the price band — comes from the IDX rules effective 8 April 2025.
Q: How do ARA and ARB affect my order on Pluang?
In two ways. First, an order priced outside the daily band is auto-rejected by the exchange, so it never reaches the queue and costs you nothing. Second, when a stock is pinned at its limit, matching can stop altogether, so an order can sit unfilled through the rest of the session even though its price looks reasonable.
Q: Why does a market order buy estimate use the ARA price?
Because they are the only prices guaranteed to be sufficient. A market order accepts whatever the exchange offers, so Pluang cannot know the cost in advance — but it does know the order can never execute beyond the daily band. Reserving at the ARA price on a buy guarantees the funds will cover it, and any difference is returned once the real price is known.