On some multi-traveler trips and on some solo trips, I sometimes have found it’s cheaper to buy two one-way tickets instead of a roundtrip ticket to do the travel. But there are also times where two separate tickets are more expensive than buying a roundtrip ticket. And there are also times where two separate tickets are as expensive as buying a roundtrip ticket for the same flights. While some markets have a particular pricing dynamic as more prevalent than in some other markets, the dynamics are not necessarily static within or across markets.