Someone on the Gen Con staff can clarify or correct this information as needed. 

I don't see any age restrictions on opening an account or buying a badge. BUT, from the Attendee Guide:

"The majority of Indianapolis hoteliers have raised their minimum guest age check-in requirements from 18 to 21 years of age. To ensure guest compliance and hotel accommodations, Management recommends that registrants under 21 either refrain from booking rooms through the housing portal or review hotel policies carefully to confirm guest age sufficiency before hotel selection. Registrants are also encouraged to carry a photo ID to present at check-in."

So if you want to create an account or just buy a badge and nothing else, I don't see an age requirement. There might be one, but I haven't found it.

If you want to do that and get a hotel, then the effective restriction imposed by the hotels (not Gen Con!) is 21 years of age. That of course is not enforced by Gen Con, but obviously you'd risk running into problems at the hotel itself. Depending on it's policy.

Again: Subject to correction by the Gen Con staff. If Mike Boozer or anyone else from there replies, listen to them! 

There is no age limit on buying a badge or having an account in your name.

If you're 11 and up you must have a badge to attend.

Under 11 you can get by with a free Wrist Band if you are only participating in KID Events.
All other Event designations require a badge.

Children ten and under are admitted free when accompanied by an attending adult. If your child wishes to participate in an event requiring an event ticket, you must purchase a Gen Con badge for them. Children over the age of ten are subject to the standard badge costs. Parents must register all children ages ten and under at the Customer Service or Badge Registration kiosks onsite for the children's protection. A wristband will be issued at that time, listing the parent or guardian’s contact information. The wristband must be attached to the child’s wrist while in the convention center in case the child and parent become separated. More information can be found in our Attendee FAQ .

Mike

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I've never read anything about this not being allowed.  I worry that having 3 children that age in the vendor hall would be a LOT to handle.  It has thousands of people, little room to walk, and space sword pirates in full regalia, and everyone is pushing their way past with large, swingy bags full of heavy stuff.  It's a lot of fun if you plan well.

Deleted, and yes children are allowed.

Mike

Thanks for the clarification!

Good to know that! Thanks! 

No age restriction for badges, but hotel policies may vary.