That depends somewhat on your personal preferences (as a couple) and sleep styles (as individuals). The queen is the most popular mattress size for couples because most average sleepers don’t need much more room than the 30 inches of sleeping space offered by the queen mattress dimensions. However, if one partner is particularly large, rolls around a lot, or loves to sprawl out, the standard queen size mattress might not be enough space. Also, if partners have different firmness requirements or one needs an adjustable bed base for better sleep, a king size bed frame will offer you the option of doing a split king by using 2 separate twin XL size mattresses. Another thing to consider is your height. If you’re well over 6 feet tall, the 80 inch queen and king may not be long enough for you. If that’s the case, you’ll probably want to consider a California King.