Prerequisites
Your trading account holds at least one perpetual contract position.
You are familiar with the "position mode" concepts: isolated margin / cross margin, as well as one-way position mode and dual (two-way) position mode.
A rejected Reduce Only order means the system detects your order's direction or size will expand or reverse your existing position exposure, instead of only reducing it. The Reduce Only feature strictly restricts orders to only decrease your existing position: no new positions or reverse opening positions are allowed. When you receive a rejection notice, the issue usually relates to your position mode, existing pending order size, or you have no reducible position left at all.
Step 1: Confirm You Have an Active Position to Reduce
[What to do]: Verify if your current position size is 0.
[How to do it]: Open the exchange's "Positions" panel, check the direction and size of the corresponding trading pair.
Scenario A: Position size is 0 → The system will reject the Reduce Only order directly. Action: You have no positions to reduce at all. If you want to open a new position, uncheck the Reduce Only option and submit a regular opening order.
Scenario B: Position size > 0 → Proceed to Step 2 to check for pending order conflicts.
[Completion Check]: The positions panel clearly shows a positive number (long position) or negative number (short position).
Step 2: Check If Unfilled Pending Orders Have Occupied Your Reduce Quota
[What to do]: Verify all unfilled limit orders to see if they have already been reserved to close out your existing position.
[How to do it]: Open the "Open Orders" page, sum up the size of all unfilled orders that are opposite to your current position direction.
The system calculates Estimated Position = Current Position + All unfilled orders (both opening and closing orders counted). If the estimated position is already 0 or about to reverse, your new Reduce Only order will be rejected.
Example: You hold a 2 BTC short position, and have already placed a 2 BTC buy limit close order. If you then submit a new 1 BTC buy Reduce Only order, the system calculates estimated position as -2 + 2 + 1 = +1 BTC, which is a reversed position, so it rejects the new order.
Scenario A: Existing pending order size ≥ Current position size → The pending orders have already reserved your full position, no new Reduce Only order is allowed. Action: Wait for the existing pending order to fill, or cancel the old order first before submitting a new one.
Scenario B: Existing pending order size < Current position size → Calculate remaining reducible quota = Position size - Existing pending order size. Action: Your new order size must be ≤ the remaining reducible quota, otherwise it will be rejected.
[Completion Check]: Confirm new order size plus existing pending order size ≤ current position size.
Critical Risk Note: Under dual position mode, failing to set the correct positionSide (LONG/SHORT) will also cause rejection. If you hold a long position but place a "BUY" direction Reduce Only order, the system will consider you are opening a new reverse position, even if you intended to close your long position: a buy order cannot reduce a long position, the correct direction is "SELL". Wrong direction will lead to direct order rejection with no extra feedback beyond standard risk alerts.
Step 3: Check Position Mode - Difference Between One-Way and Dual Position Mode
[What to do]: Confirm if you are using one-way position mode or dual position mode, as Reduce Only rules differ across the two modes.
[How to do it]: Find the "Position Mode" option in your futures settings page.
Scenario A: One-way position mode → Reduce Only is a standard supported feature, you can enable it directly, and the estimated position logic in Step 2 fully applies.
Scenario B: Dual position mode → The order logic is stricter under dual mode. You need to explicitly specify positionSide (LONG or SHORT), and the position direction is calculated independently. Action: If you hold a long position, the closing order direction is "SELL", and positionSide should be set to "LONG"; if you hold a short position, the closing order direction is "BUY", and positionSide should be set to "SHORT". Wrong direction setting will lead to immediate rejection.
[Completion Check]: Confirm your current position mode, and verify the new order's direction and positionSide fully match your existing position.
Common Rejection Causes
Many users submit a new manual Reduce Only close order when there are still unfilled take-profit orders in their account. The system judges "existing pending order size + new order size > current position" and rejects the new order directly. This is an extremely common error in reduce-only logic: you think you are executing partial take-profit, but the system considers you are over-closing your position. The correct practice is to go to the "Open Orders" page to cancel the old order or adjust its size first, then place your new order.
Post-Submission Validation
After your Reduce Only order is placed successfully, go to the "Open Orders" page to confirm the order is marked with the "Reduce Only" tag, and its status shows "Placed" or "Active". Open the positions panel to confirm the new order's size is reflected in the estimated position calculation. On exchanges like Bybit, the positions panel will show a "Close pending order exists" reminder.
Next Steps
If your Reduce Only order is repeatedly rejected for "estimated position equals 0", check your open orders page for old pending orders that have occupied your reduce quota, cancel them and resubmit. You can also refer to official help center documents from major exchanges for Reduce Only rules on estimated position calculation and zero-position rejection troubleshooting.
