How to phrase a casual reception on an invitation

I Do BBQ?

Are you bringing in caterers for the pig roast?

Some of the information on the invite may make it easy to determine that is more casual. Location and formality of the invitation generally speak to if an event is formal, semi formal or casual. I wouldn't put that its a casual reception on the invitation. You can note that on the website if you would like for guest to learn more information. In theory you could put "casual reception to follow" but i dont think as a guest i'd know what that means. Do you want them to dress casually? If so thats something that would go on the website as a heads up or maybe by word of mouth.

I see on some invites people post things like "Dinner and Dancing to follow" or "Spirts, Refreshments & Merriment to follow." can you write something like "Barbecue, Brews, and Games after ceremony" Use a casual style of invitation. Maybe on an insert card indicate that things will take place on grass so people know not to wear heels.