How big is the Subaru Outback gas tank?

The gas tank on the Subaru Outback is 18.5 gallons (about 70 liters) in current models.

That fixed capacity helps determine driving range, but actual miles per tank depend on the engine choice, driving conditions, and individual driving habits. Here’s a detailed look at the tank size and what it means in practice.

Tank size in current and recent Outback models

Key figures for the tank size across current Outback models:

• Current generation (2020–present) Outbacks list a fuel tank capacity of 18.5 gallons (70 L).


• Turbocharged variants (2.4-liter engine) retain the same 18.5-gallon capacity as the base engine.


• The capacity is consistently cited across trims within the modern generation, with only minor rounding differences in some markets.

In practical terms, a full tank will yield a broad driving range depending on engine efficiency and conditions. For example, EPA-tested figures and typical real-world driving suggest roughly 425–537 miles per tank across the two main engine setups, before considering factors like speed, terrain, and cargo load.

Estimated range by engine type

With the 2.5-liter base engine, the Outback often posts an EPA combined rating near 29 mpg, which translates to about 537 miles per 18.5-gallon tank under ideal conditions. With the 2.4-liter turbo, the combined rating is closer to the mid-20s, yielding roughly 425 miles per tank. Real-world range will vary, commonly falling within the 350–550 mile band depending on driving style and road conditions.

What this means for real-world driving

For daily use and long trips alike, 18.5 gallons gives the Outback a comfortable range before refueling, especially on highways where higher mpg boosts total miles per tank. If you routinely drive in city conditions or steep terrain, expect a shorter real-world range per tank, even though the official tank size remains the same.

Summary

The Subaru Outback currently uses an 18.5-gallon (70-liter) gas tank across its modern lineup, including both the base 2.5-liter engine and the turbocharged 2.4-liter option. This fixed capacity, combined with each engine’s fuel economy, typically yields a wide range per tank—from roughly 425 miles on the turbo model to about 537 miles on the 2.5-liter version, with real-world results influenced by driving conditions. In short: you’ll rarely be short of miles between fills, but your actual range will reflect how you drive and where you drive.

How many gallons of gas does a 2017 Subaru Outback hold?

A 2017 Subaru Outback has a fuel tank capacity of 18.5 gallons, regardless of the trim or engine. This capacity applies to all models of the 2017 Outback.
 

• Capacity: 18.5 gallons 
• Fuel type: Regular unleaded or 87-octane fuel 
• Note: While higher-octane fuel won't harm the engine, it doesn't provide performance benefits for this vehicle. 

How far can a Subaru Outback go on a full tank of gas?

A Subaru Outback can go between approximately 426 and 518 miles on a single tank of gas, depending on the model and driving conditions. The exact range varies by trim, with the standard engine models getting a longer range and the turbocharged XT and Wilderness trims having a shorter range. 
Estimated range by trim

• Standard 2.5L Engine: Can get up to 518 miles per tank, based on its EPA-estimated combined fuel economy.
• Turbocharged XT or Wilderness Trims: Can get up to 462 miles (XT) or 426 miles (Wilderness) per tank, due to a less efficient engine. 

Factors that affect your actual range

• Driving style: Aggressive acceleration and braking will decrease your gas mileage. 
• Driving conditions: City driving typically results in lower mileage than highway driving. 
• Terrain: Driving in mountainous areas will lower your MPG. 
• Vehicle maintenance: Things like tire pressure and engine cleanliness can affect efficiency. 
• Fuel quality: The quality of the fuel you use can also play a role. 

How big is a Subaru Outback gas tank?

A Subaru Outback has an 18.5-gallon fuel tank capacity across all current models and trims. This size is consistent for recent model years, including the 2023 and 2025 versions, and allows for a driving range that varies based on engine type and driving conditions. For example, a 2025 model with the 2.5L engine has an estimated highway range of up to 518 miles, while the XT models with the turbocharged engine have a different range based on their fuel economy.
 

• Tank Size: 18.5 gallons 
• Consistency: The 18.5-gallon capacity is standard across all trim levels of recent models. 
• Example Range (2025): The 2.5L engine can achieve up to 518 miles on the highway, while the XT models with the 2.4L turbo engine have a different estimated range based on their fuel economy. 
• Note: Your actual driving range will vary depending on your driving habits and road conditions. 

What year was a bad year for the Subaru Outback?

Years to avoid for the Subaru Outback include 2010–2014, which had widespread CVT, oil consumption, and oil leak issues, and 2018, which had recalls and reliability concerns. Additionally, some sources recommend avoiding the 2005–2007 models due to head gasket problems and the 2020 model, which had electrical and windshield issues. 
Years to avoid

• 2010–2014: These models are frequently cited for significant transmission issues (CVT), oil consumption, and general reliability problems. The 2010 model specifically had issues with the torque converter locking up. 
• 2018: This year saw recalls and owner complaints related to oil consumption, exhaust components, and electrical issues. 
• 2005–2007: These models are known for head gasket failures, which can cause coolant and oil leaks. 
• 2020: This model year is associated with a high number of electrical problems, including dead batteries and stalling, as well as issues with the windshield cracking from small chips. 

Other potential problem years

• 2013: Frequently mentioned for oil consumption issues.
• 2015: Some reports list it with electrical and engine problems.
• 2017: Reliability issues were noted.