This is for everyone who's ever ordered a side of guacamole expecting it to be free. It never is. Except for today.  Chipotle is letting customers order the luxury item free of charge for one day only.

The Mexican fast food chain announced the free guacamole offer for Wednesday, July 31, or otherwise known as National Avocado Day.

The offer is good for one free topping of guacamole with the purchase of any regular-priced item when ordering through Chipotle's mobile app or website, according to the chain's website.

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The offer is limited to one free guacamole per entree, and offer is subject to availability.

Chipotle also said that the offer can be used for any entree that is redeemed as a Chipotle Rewards meal, meaning your burrito bowl with guac, for example, could be free but only if you've collected enough rewards credits.

You can get full details on the offer here.