Market orders are not allowed. Try placing a limit order.
Last updated 30 June 2026
Market orders are not allowed
This error comes from your broker, not from AutoTrader Web. Under a recent rule from the market regulator (rolling out from April 2026) for orders placed through a trading API, many brokers no longer accept plain MARKET orders and accept only LIMIT orders. AutoTrader Web has a built-in feature, Market Price Protection (MPP), that handles this for you: you keep placing market orders as usual, and it converts them into a limit order at a price near the live price, with a small safety buffer so they still fill. Turn it on in Settings → General (choose Small, Normal or Aggressive; Normal suits most users). You can also place a LIMIT order yourself instead of a MARKET order.
When this happens
- 1 Under a recent market regulator rule (rolling out from April 2026) for orders placed through a trading API, your broker no longer accepts plain MARKET orders and accepts only LIMIT orders.
- 2 Some brokers also block MARKET orders on volatile or low-liquidity contracts to protect you from a bad fill.
You see this error while placing an order. AutoTrader Web sends the order to your broker, and the broker returns this message. The wording can differ a little by broker (for example “Market orders are not allowed. Try placing a limit order.” or “market orders are not permitted”), but the cause and fix are the same.
Why this happens
The main reason is a recent rule from the market regulator. Under the newer rules for orders placed through a trading API (rolling out from April 2026), many brokers no longer accept plain MARKET orders and accept only LIMIT orders. AutoTrader Web places your orders through your broker’s API, so your orders come under this rule. Different brokers have been switching this on at different times, so you may see it on one broker but not yet on another.
A second, older reason is contract-level protection: some brokers already blocked plain MARKET orders on volatile or low-liquidity contracts, where a market order could fill at a price far from what you expect.
In both cases this is a rule on the broker’s side, not on ours, and the fix is the same.
The easy fix: Market Price Protection (MPP)
AutoTrader Web has a built-in feature called Market Price Protection (MPP) that solves this for you. With MPP on, you keep placing market orders the same way as before — you do not have to pick a price. Behind the scenes, AutoTrader Web converts your market order into a limit order at a price near the live price, with a small safety buffer so it still fills quickly.
To turn it on:
- Open Settings → General.
- Set Market Price Protection (MPP) to Small, Normal or Aggressive. Normal suits most users. A bigger buffer fills more easily in fast markets but may fill at a slightly worse price.
- Save. Now your market orders go through as protected limit orders.
For full details, see the Market Price Protection (MPP) guide.
The manual way: place a limit order yourself
If you prefer, you can place a limit order yourself instead of using MPP:
- In the order window, change the order type from MARKET to LIMIT.
- Set a price for the order.
- If you want the order to fill quickly (like a market order would), set the limit price close to the current market price — a little higher for a buy, a little lower for a sell.
- Place the order again.