TOP 3 least crowded Seoul subway lines in 2025: Line 6, Line 1, Line 3

First, conclusion: Top 3 routes in terms of congestion in 2025

Among the 2025 CSV values by route, the lowest is Line 6 at 112.9. Next is Line 1 at 126.3, Line 3 at 130.8, and Line 5, which is in fourth place, at 131.3. The difference between Line 3 and Line 5 is as small as 0.5, so it is difficult to say that there is a very large perceived difference based on ranking alone.

In this comparison, the overall average of 137.0 was excluded from the route ranking. The bottom three are all below average, but that fact alone doesn't guarantee empty seats. The annual average route-level indicators are background information for reference when planning a route, and are not a congestion forecast for a specific train.

• 1st (lowest) Line 6: 112.9
• 2nd Line 1: 126.3
• 3rd Line 3: 130.8
• 4th Line 5: 131.3 — 0.5 difference from 3rd place

Lowest Line 6 112.9: 24.1 below average

Line 6's 112.9 is 24.1 lower than the overall 2025 average of 137.0 provided. Compared to the average, this value is approximately 17.6% lower. When compared to Line 9's 182.5, which is the highest in the same data, there is a difference of 69.6. This is the obvious reason why it is the lowest among the 11 routes.

However, this does not mean that you can comfortably ride on any section of Line 6 and at any time. Congestion varies depending on the transfer station, vicinity of the event venue, commuting direction, and train intervals. Especially for important schedules, route search and checking the platform electronic display right before departure are much more reliable criteria than assuming that “it’s okay because it’s Line 6.”

2nd Line 1 126.3: Distinguishing between low and high volatility

Line 1 was 126.3, 10.7 lower than the overall average. If you look at the numbers alone, it is in the bottom tier, but as the route is long and the connection sections and purposes of use are diverse, it is difficult to simplify the experience of a specific section. Since this data is one annual value per route, it does not distinguish between crowded stations or directions.

So when using Line 1, look at the entire route to your destination rather than just “the annual numbers are low.” If you have a route that involves less transfers or less walking, it may actually be easier for you. If you can choose a departure time, leave plenty of time. If you are a traveler, check the station name and next station to avoid making a mistake.

3rd place Line 3 130.8: Meaning of 0.5 difference from Line 5

Line 3 is the third lowest at 130.8, and the difference with the next ranked Line 5 at 131.3 is 0.5. This means that there is a weak basis for reading the dichotomy, “Line 3 is definitely quiet and Line 5 is not.” Routes with similar numbers should be viewed in the same category rather than ranked, and individual travel conditions should be considered more important.

When reading statistics, it is important not to exaggerate small differences. The raw data has one decimal place and does not provide distribution by time zone, direction, or station. The 0.5 difference is only a slight difference in the annual route average, and is not a number that predicts the level of congestion in the car I will ride today.

• Difference between Line 6 and Line 1: 13.4
• Difference between Line 1 and Line 3: 4.5
• Difference between Line 3 and Line 5: 0.5
• The smaller the difference, the more important the real-time route/direction is.

Why You Shouldn’t Turn “Less Crowded” into Guaranteed Seats

Congestion is expressed as a single number, but the user's experience is created by combining train spacing, platform waiting, transfer passageways, exit stairs, and companions' luggage. Even routes with a low annual value can be sufficiently crowded during rush hour or after large events, and conversely, routes with a high annual value can also be traveled relatively comfortably during off-peak times.

So you shouldn't use these rankings as a secret to getting a seat or a guarantee to avoid crowds. A better use would be as a hint when comparing alternative paths. If there are two routes with similar travel times, it makes sense to look at the annual indicators, number of transfers, walking distance, and real-time guidance and choose the one that is more convenient for you.

Simple steps to apply to actual route selection

First, enter your departure station and exact destination into the map app, and compare two or three recommended routes instead of just one. Next, look at the number of transfers, total steps, and arrival time. At this time, if the alternative route includes lines 6, 1, and 3, refer to the annual statistics in this article, but also weigh the difference in minutes and baggage and travel conditions.

Finally, after arriving at the station, you should check the train's destination and next station rather than the route name. A low congestion rating doesn't prevent you from making the mistake of taking a train in the opposite direction. On the platform, it is safer to check the current route between the electronic signs, signs, and app, and not to force the ride in front of crowded doors.

• Compare two or three real-time routes by origin and destination
• Compare transfer, walking, and arrival times first
• Consult annual congestion rankings only for similar routes
• On the platform, check your destination and next station again.

Analysis scope and reproduction method

This article used the 2025 row from the provided “Seoul Subway Congestion Statistics” CSV. Excluding the “Average” column, we sorted the values ​​for the 11 routes in ascending order and selected Line 6 at 112.9, Line 1 at 126.3, and Line 3 at 130.8. No additional weights, predictions, or station-specific data were added.

This is not a ranking of Seoul's entire rail network, including routes not listed in the CSV column. Additionally, results may change as public data is updated or the scope of the aggregation changes. If you want to check the numbers again, open the latest data from the original Seoul Open Data Plaza below and sort it by the same criteria.