2 One-Ways or a Round-Trip: Which Costs Less? [2025 Study]

When planning a trip, travelers often debate whether to book a round-trip ticket or 2 separate one-way flights. To settle this question, we analyzed airfare data across 5 of the busiest domestic routes in the U.S., comparing prices for round-trip tickets versus 2 one-ways over a 1-week period. By examining 8 major airlines, this study reveals the savings (or lack thereof) associated with each option, helping you make more informed booking decisions.

Round-Trip Flights Save You 33% Compared to 2 One-Ways

When it comes to saving money on airfare, booking a round-trip ticket is the clear winner. On major U.S. routes over a 1-week period, the average cost of 2 one-way tickets was $432, while a round-trip flight averaged just $291. That’s a $141 difference, or roughly 33% in savings, highlighting why round-trip bookings are the smarter choice for budget-conscious travelers.

We’ll break this down further by airline, day of the week for booking, and specific routes to uncover where and how travelers can save the most. 

Cost Differences: 2 One-Ways vs. Round-Trip by Airline

To better understand how booking a round-trip ticket compares to purchasing 2 one-way flights, we analyzed fare data from 8 major U.S. airlines. For each airline, we calculated the average costs for 2 one-way tickets (departure and return) and compared them to the average cost of a round-trip ticket on the same routes and travel dates. This comparison highlights the percentage savings offered by booking round-trip fares and which airlines offer the greatest savings.

Key Findings by Airline:

• United provides the greatest percentage savings, with round-trip fares averaging 39% cheaper ($163 less) than 2 one-way tickets.
• JetBlue offers the smallest savings, with round-trips costing only 4% less ($20 cheaper) than 2 one-way flights.
• Airlines like Alaska and American also show significant savings, with round-trip tickets averaging 34% and 32% cheaper, respectively.
• Budget carriers like Frontier and Spirit offer modest savings, with round-trips averaging 12.5% ($27 less) and 8.6% ($17 less), respectively.
• Southwest fares land in the middle, offering 15.7% savings on round-trip bookings ($43 less).

These results underscore how much savings can vary by airline, making it important for travelers to consider their carrier when deciding between 2 one-ways or a round-trip.

Cost Differences: 2 One-Ways vs. Round-Trip by Day of the Week

Interestingly, the day of the week you choose to fly can significantly impact the cost difference between booking 2 one-way tickets and a round-trip fare. We analyzed average airfare costs for departures across all 7 days of the week to determine which offers the greatest savings.

Key Findings by Day of the Week:

• Wednesday departures provide the greatest dollar savings for round-trip bookings, with fares averaging 43% cheaper ($153 less) than 2 one-way tickets.
• Tuesday flights follow closely, with round-trips costing 42% less ($146 less) than 2 one-ways.
• Friday departures yield the smallest dollar savings, with round-trips averaging 35% cheaper ($110 less).
• While Sunday departures see higher overall costs, the savings on round-trip tickets remain consistent, averaging 25% cheaper ($147 less).

These trends suggest that midweek departures, particularly on Tuesdays and Wednesdays, are the most cost-effective days to book round-trip tickets. Travelers flying on weekends may face higher overall prices and more modest percentage savings.

Cost Differences: 2 One-Ways vs. Round-Trip by Major Airport Routes

The cost savings between 2 one-way flights and a round-trip ticket also depend on the specific route. We analyzed fares across 5 of the busiest domestic airport routes to identify where round-trip bookings offer the most value.

Key Insights by Route:

• Los Angeles (LAX) to San Francisco (SFO) offers the largest savings, with round-trip fares averaging 42% cheaper ($143 less) than 2 one-way tickets.
• New York (JFK) to Los Angeles (LAX) has the highest overall costs and offers the smallest percentage savings, with round-trips costing 26% less ($160 cheaper) than 2 one-ways.
• New York (LGA) to Chicago (ORD) shows round-trip fares averaging 30% cheaper, saving travelers $124 compared to 2 one-way flights.
• Atlanta (ATL) to New York (LGA) offers savings of 32% on round-trip fares, at $112 less than 2 one-ways.
• Denver (DEN) to Chicago (ORD) offers 30% savings, with round-trip tickets costing $123 less than booking 2 one-ways.

Across all analyzed routes, round-trip tickets consistently provide cost advantages, though the degree of savings varies. Shorter routes like LAX to SFO often yield the highest percentage savings, while longer cross-country routes like JFK to LAX show smaller relative savings but still offer significant dollar value reductions.

Methodology

To determine the cost differences between booking 2 one-way flights versus a round-trip ticket, we analyzed fares for a 5-day trip across 5 of the busiest domestic flight routes. Our study examined flight prices over a 1-week period (Monday through Sunday) using data from 8 major airlines. For each route and travel date, we compared the total cost of 2 one-way tickets (departure and return) with the cost of a round-trip ticket for the same itinerary. 

Final Thoughts

For most travelers, booking a round-trip ticket offers significant savings compared to purchasing 2 one-way flights. However, the savings vary depending on the airline, departure day, and route. Understanding these factors can help you optimize your travel budget and avoid unnecessary expenses.

With this insight, you can book your next trip with confidence, knowing you’ve chosen the option that works best for your wallet.