The great thing about chimichurri is that you can make it ahead and it tastes better after a day or two in the fridge. The longer it sits, the more flavor it has. Chimichurri will last in the fridge in a sealed container for 5-7 days. The olive oil will harden in the fridge, so you need to bring it to room temperature before serving. You can also freeze chimichurri for up to 3 months.