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Chicago → San Diego flights

Chicago–San Diego fares have run a median of $117 over 12 snapshots; most deals sit $117–$170, so book once you see that range.

Fares cluster near $117 — but outliers spike to $399

Key takeaways

Median fare is $117, and the bottom quartile sits right at that same $117 mark — a strong signal of where the real floor is.
Middle 50% of fares fall between $117 and $170, a reasonable target range for a solid deal.
High-end outlier of $399 shows occasional spikes well above typical pricing — likely a last-minute or low-availability fare.
Spread of 287% is large, but driven mostly by that one high outlier rather than a consistently volatile market.
Only 12 snapshots means this read is directional, not a precise seasonal pattern.

30-day price trend

ORD → SAN · cheapest cached fare per day · last 13 days · ↓ 73%

$103 low$399 high

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

The full picture

The data shows a fairly tight cluster of everyday fares for Chicago to San Diego, with a median of $117 and a 25th-to-75th percentile band of just $117–$170. That narrow core suggests most travelers booking on a normal timeline should expect to land somewhere in that range. The headline spread of 287% looks dramatic, but it's almost entirely explained by a single high-end snapshot at $399 — not a market that's broadly unpredictable day to day.

With only 12 snapshots in this sample, we can't responsibly map out a precise booking curve or claim prices "soften" at a specific point in the horizon. What we can say is that the bulk of observed fares — including the entire bottom quartile — sit at or near the $117 floor, which implies that low fares are fairly available rather than rare flash sales. The $399 outlier is a useful reminder that waiting too long or searching during a constrained-inventory moment can push you well outside the typical range, even on a route that otherwise prices consistently.

We don't have enough signal in this dataset to identify a dominant carrier or a reliable day-of-week pattern, so we won't speculate on either. The practical takeaway: treat anything at or near $117–$130 as a good fare worth booking, and treat prices climbing toward $200+ as a sign to wait or recheck rather than panic-buy. The honest caveat here is sample size — 12 days of snapshots is enough to see a rough shape of pricing, but not enough to make confident claims about seasonality, weekly cycles, or exactly how far in advance to book.

Ready to look at fares?

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

Related travel pages

Why we regenerated this article: Median fare ↓ 31% ($170 → $117). 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.