Paper Trading Buy Price Error


Today while buying BRPA I noticed that the buy prices were completely off

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I have confirmed with other sources including polygon that the prices at these times were around 38 dollars and 33 dollars respectively

Any reason why the paper trading buy price would be so different?

Paper trading simulates the fill prices as the NBBO bid/ask quote at the time of the order. For a buy, the fill price is the current ask. For a sell, it is the current bid. These may not be the same as traded prices around the the time of order.

Paper trading doesn’t do a great job of simulating prices for very low liquidity equities such as BRPA partly because the bid/ask spreads are often very large. On the other hand, the BRPA trade above could very well have taken place. It is very common for market orders to fill at, or just a bit better, than the current quote. For this reason, especially with low volume stocks, it’s advisable to always place limit orders to ensure one gets a price one expected.