Originally Posted by
jerry a. laska
The amex companion voucher specifically allows you to take someone outside of your household as the companion, but you cannot book with someone outside the household online, you must call.
And this is also true for the U.S. Chase companion voucher (officially known as the "Travel Together Ticket"). Companions do not need to be household members, but a phone call is required. The T & C's are quite clear about this, and I have done it several times myself.