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Seattle → Chicago flights

Seattle–Chicago fares have hovered near a $161 median over the past 12 snapshots; watch for dips into the $139–$141 range.

Fares cluster near $161 — but it's a thin sample, so stay flexible

Key takeaways

Median fare is $161, with a observed range of $139 to $198
Bottom quartile prices sit at or below $141, close to the 30-day low
Top quartile fares start around $195, nearly matching the ceiling of $198
A 42% spread between low and high signals real volatility, not a stable fare floor
Only 12 snapshots were sampled, so patterns here are directional, not definitive

30-day price trend

SEA → ORD · cheapest cached fare per day · last 13 days · ↓ 12%

$139 low$198 high

See full numbers and stats on the SEA → ORD price history page.

The full picture

The data shows a fairly wide spread for this route — a 42% gap between the $139 low and $198 high, with a median of $161. That spread suggests fares aren't locked into a narrow band; travelers willing to track prices for a bit have historically found meaningfully cheaper options than the median, since the bottom quartile ($141) sits close to the observed floor.

With only 12 days of snapshots, this dataset is too thin to confidently map out a booking-window curve — we can't say with precision whether prices soften weeks out or spike closer to departure. What we can say is that roughly a quarter of observed fares came in at or under $141, and roughly a quarter came in at $195 or more, so there's a real gap between opportunistic and last-minute pricing on this route. That's useful for setting expectations: if you see something near $140-$150, it's in line with the cheaper end of what's been observed; if you're quoted near $195+, you're paying premium-end pricing for this market.

No dominant carrier or weekly pattern is visible in the data provided, so we can't make claims about specific airlines or days of the week being more favorable. The honest caveat here is sample size: 12 snapshots is a small window, and a 42% spread on that little data means the true range could be wider or narrower than what we've captured. Treat the $161 median as a reasonable benchmark, but verify closer to your travel dates rather than anchoring hard to any single number.

Ready to look at fares?

Search SEA → ORD on Aviasales →See the price history →

Related travel pages

Why we regenerated this article: Bottom quartile ↓ 12% ($161 → $141). We only rewrite when the underlying price index actually moves — stable weeks keep the previous take.

AI-authored from this route's 30-day price index. Article last regenerated Oct 10, 2026. Fares shift continuously — confirm at booking.