What is positive Slippage and negative Slippage?

Slippage can take on a positive, neutral, or negative form. This can produce results of execution that are more favourable, equal to, or less favourable than the intended execution price.

The final execution price vs. the intended execution price can be categorised as positive Slippage, no Slippage or negative Slippage.

Positive Slippage occurs when the execution price surpasses the intended price.
For instance, if a buy order has a preset take profit at 100, but the final execution price is 100.5, it results in positive Slippage.

No Slippage occurs when the execution price matches exactly the intended price.
For instance, if a buy order has a preset take profit at 100, but the final execution price is 100, it results in no Slippage.

Negative Slippage occurs when the execution price is worse than the intended price.
For instance, if a buy order has a preset take profit at 100, but the final execution price is 99.5, it results in negative Slippage.