Chicago to San Juan MDW, ORD, RFD → SJU
Chicago Midway International Airport (MDW), O'Hare International Airport (ORD), Chicago Rockford International Airport (RFD) → Luis Munoz Marin International Airport (SJU)
The cheapest return found recently is $196 with Frontier Airlines, 5 Dec – 12 Dec, found today. The cheapest one-way found recently is $363 with Allegiant Air, 16 Jan 2027, found yesterday.
Return
The cheapest return fare on each of 6 departure dates is usually $258 to $359.
Cheapest return found recently
$196
5 Dec – 12 Dec · Frontier Airlines
Chicago Midway International Airport (MDW) → Luis Munoz Marin International Airport (SJU)
Leaves 12:28 p.m. · Return leaves 5:01 a.m. · 19 h 11 min of travel, both ways together
out 1 stop, back 1 stop
found today
Cheapest nonstop return
$248
17 Jan 2027 – 5 Feb 2027 · United Airlines
O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU)
Leaves 2:16 p.m. · Return leaves 8:25 a.m. · 10 h 8 min of travel, both ways together
out nonstop, back nonstop
found 5 days ago
Found recently, and the cheapest we hold
$196 5 Dec – 12 Decfound todaySee prices for these dates
It is also the cheapest return we hold, of any age.
What have prices looked like?
Over 25 days, 24 Sept to 18 Oct, the cheapest return we saw each day was $148 to $409.
25 days is a short history, so treat this range as an early guide.
Those were the prices on those days, not today's.
Is this a good return price?
Compared with the cheapest return fare on each of 6 departure dates from 5 Dec to 6 Apr 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other 7-night return fares leaving within 3 days of 5 Dec to compare.
Every date we hold
13 fares on 6 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 5 Dec – 12 Dec | $196 | Frontier Airlines | Chicago Midway International Airport (MDW) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found today | See prices for these dates |
| 23 Dec – 1 Jan 2027 | $632 | Frontier Airlines | O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 17 Jan 2027 – 5 Feb 2027 | $248 | United Airlines | O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU) | out nonstop, back nonstop | found 5 days ago | See prices for these dates |
| 18 Jan 2027 – 25 Jan 2027 | $323 | Frontier Airlines | O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU) | out nonstop, back 1 stop | found yesterday | See prices for these dates |
| 27 Jan 2027 – 31 Jan 2027 | $371 | Southwest Airlines | Chicago Midway International Airport (MDW) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found 2 days ago | See prices for these dates |
| 6 Apr 2027 – 13 Apr 2027 | $287 | American Airlines | O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found 3 days ago | See prices for these dates |
Which month looks cheapest?
December 2026 is the cheapest month — from $196.
Airlines on the cheapest dates: Frontier Airlines, United Airlines, Southwest Airlines, American Airlines.
One-way
The cheapest one-way fare on each of 4 departure dates is usually $108 to $431.
Cheapest one-way found recently
$363
16 Jan 2027 · Allegiant Air
Chicago Rockford International Airport (RFD) → Luis Munoz Marin International Airport (SJU)
Leaves 10:45 a.m. · 45 h 56 min trip
3 stops
found yesterday
Cheapest nonstop one-way
$100
11 Jan 2027 · Frontier Airlines
O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU)
Leaves 10:31 p.m. · 4 h 42 min trip
nonstop
found 2 days ago
Found recently, and the cheapest we hold
$363 16 Jan 2027found yesterdayOpen this trip
$100 11 Jan 2027found 2 days agoOpen this trip
What have prices looked like?
Over 25 days, 24 Sept to 18 Oct, the cheapest one-way we saw each day was $100 to $157.
At $363, the cheapest one-way found recently is above that range.
25 days is a short history, so treat this range as an early guide.
Those were the prices on those days, not today's.
Is this a good one-way price?
Compared with the cheapest one-way fare on each of 4 departure dates from 15 Dec to 16 Jan 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
Yes. Among one-way fares leaving within 3 days of 16 Jan 2027, 13 Jan 2027 costs $110: $253 less than the cheapest found recently.
Frontier Airlines · O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU) · nonstop · found 6 days ago
Every date we hold
7 fares on 4 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 15 Dec | $634 | Allegiant Air | Chicago Rockford International Airport (RFD) → Luis Munoz Marin International Airport (SJU) | 3 stops | found 3 days ago | Open this trip |
| 11 Jan 2027 | $100 | Frontier Airlines | O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU) | nonstop | found 2 days ago | Open this trip |
| 13 Jan 2027 | $110 | Frontier Airlines | O'Hare International Airport (ORD) → Luis Munoz Marin International Airport (SJU) | nonstop | found 6 days ago | Open this trip |
| 16 Jan 2027 | $363 | Allegiant Air | Chicago Rockford International Airport (RFD) → Luis Munoz Marin International Airport (SJU) | 3 stops | found yesterday | Open this trip |
Which month looks cheapest?
January 2027 is the cheapest month — from $100.
Airlines on the cheapest dates: Allegiant Air, Frontier Airlines.
Premium cabin fares from Chicago to San Juan
We hold no premium economy, business or first-class fares for this route: we collect them for the busiest routes, and this one is not among them yet.
Today's prices for 5 Dec – 12 Dec in another cabin: Premium economy · Business · First
Today's prices for 16 Jan 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Chicago to San Juan?
Return
Fares 7 to 13 days before departure were typically 21% lower than 0 to 6 days before departure.
From the cheapest return each day between 24 Sept and 18 Oct (25 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 0–6 days | $264 | $208 | +27% | 12 |
| 7–13 days | $208 | $206 | Cheapest seen | 8 |
| 14–29 days | $214 | $197 | +3% | 14 |
| 30–59 days | $216 | $148 | +4% | 18 |
| 60–89 days | $218 | $188 | +5% | 20 |
| 90–179 days | $340 | $248 | +64% | 25 |
| 180+ days | $328 | $308 | +58% | 19 |
One-way
The cheapest fares were 30 to 59 days before departure.
From the cheapest one-way each day between 24 Sept and 18 Oct (25 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 30–59 days | $100 | $100 | Cheapest seen | 10 |
| 60–89 days | $106 | $100 | +6% | 10 |
| 90–179 days | $157 | $110 | +57% | 12 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
South Bend → San Juan
116 km from Chicago
$738
$542 more than flying from Chicago
12 Feb 2027 – 21 Feb 2027 · SBN → SJU · out 1 stop, back 1 stop
found 4 days ago
Cheapest recent price on each route — round trip, per traveler in Economy. Distances are in a straight line.
Live price for these dates
The cheapest return found recently is for 5 Dec – 12 Dec. A live search on this page shows what those dates cost now, for one adult in economy.
Prices are what travelers' searches on Aviasales found in the last 7 days, in US dollars: the price the seller showed on Aviasales; bags may cost extra. Fares change, so check today's price before you book. How our prices work