Is a 3 or 6 month subscription charged up front?Updated 3 years ago

Yup. You're charged the full cost of all the boxes at the time of purchase. 

Multi-month subscription are discounted, compared to the 1 month subscriptions.

Also, all subscriptions auto-renew. If you would like to cancel the auto-renew, simply log into your account after you have placed an order and cancel the subscription. The cancellation will go into effect after your last box in the subscription goes out.