You find a flight to Lisbon for $380 round trip. The hotel looks perfect. Then you click through and see the price jump by $400 because you are one person. That is the single supplement, and it is the most annoying tax on independence in the travel industry. For 2026, the math has changed. More tour operators have built solo-specific departures. More hotel chains have killed the supplement on certain room types. And the flight search engines have finally stopped hiding basic economy fares from solo travelers. Here is how to keep your money. What Actually Counts as a Solo…