$140 Cheap flight deals from St. Louis (STL) to Great Diamond Island (PWM)

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Airfares from $140 One Way, $275 Round Trip from St. Louis to Great Diamond Island

Prices starting at $275 for return flights and $140 for one-way flights to Great Diamond Island were the cheapest prices found within the past 7 days, for the period specified. Prices and availability are subject to change. Additional terms apply.

Fri, Sep 25 - Wed, Sep 30
STL
St. Louis
PWM
Portland
$275 Roundtrip, found 1 day ago
$275
Roundtrip
found 1 day ago
Select Delta flight, departing Fri, Sep 25 from St. Louis to Portland, returning Wed, Sep 30, priced at $275 found 1 day ago
Mon, Sep 21 - Sat, Sep 26
STL
St. Louis
PWM
Portland
$275 Roundtrip, found 2 days ago
$275
Roundtrip
found 2 days ago
Select United flight, departing Mon, Sep 21 from St. Louis to Portland, returning Sat, Sep 26, priced at $275 found 2 days ago
Mon, Sep 21 - Sat, Sep 26
STL
St. Louis
PWM
Portland
$276 Roundtrip, found 2 days ago
$276
Roundtrip
found 2 days ago
Select Southwest Airlines flight, departing Mon, Sep 21 from St. Louis to Portland, returning Sat, Sep 26, priced at $276 found 2 days ago
Mon, Sep 21 - Fri, Sep 25
STL
St. Louis
PWM
Portland
$281 Roundtrip, found 2 days ago
$281
Roundtrip
found 2 days ago
Select Southwest Airlines flight, departing Mon, Sep 21 from St. Louis to Portland, returning Fri, Sep 25, priced at $281 found 2 days ago
Tue, Aug 4 - Tue, Aug 11
STL
St. Louis
PWM
Portland
$281 Roundtrip, found 16 hours ago
$281
Roundtrip
found 16 hours ago
Select American Airlines flight, departing Tue, Aug 4 from St. Louis to Portland, returning Tue, Aug 11, priced at $281 found 16 hours ago

Great Diamond Island economy flight packages

Price found within the past 48 hours. Click for updated prices.
Inn at Diamond Cove
3.5-star property

Inn at Diamond Cove

8.8/10 Excellent! (198 reviews)

Aug 13 - Aug 16

3 night stay

St. Louis (STL) to Portland (PWM)

American Airlines • Non-stop roundtrip • Coach
Save 100% on your flight
Price was $1,204, price is now $826 per person
$826
per person
found 1 day ago
The manager and the staff were amazing - we had an issue with the air conditioning in our room and they were very helpful and got us moved to another room. I wish there were some more options for food, and was disappointed that the bar was not staffed, but the inn was beautiful and the atmosphere relaxing!

Reviewed on Jul 4, 2026

Blind Tiger Portland - Danforth Street.
3.5-star property

Blind Tiger Portland - Danforth Street.

9.6/10 Exceptional! (188 reviews)

Aug 22 - Aug 26

4 night stay

St. Louis (STL) to Portland (PWM)

United • Non-stop roundtrip • Coach
Save 100% on your flight
Price was $1,576, price is now $1,116 per person
$1,116
per person
found 21 hours ago
We were only there for 1 night, but the innkeeper made a great suggestion for dinner. Overall a great place and would stay again.

Reviewed on Jun 26, 2026

Portland Harbor Hotel
4.0-star property

Portland Harbor Hotel

9.4/10 Exceptional! (1,775 reviews)

Aug 25 - Aug 29

4 night stay

St. Louis (STL) to Portland (PWM)

Delta • Non-stop roundtrip • Coach
Save 100% on your flight
Price was $1,365, price is now $1,040 per person
$1,040
per person
found 22 hours ago
Only 4 rooms that were having A/C problems. Of course we had one the rooms. If the A/C isn’t working, why continue to reserve the rooms and not just fix the A/C??? Front desk attendant Dennecia was wonderful and was able to get us moved for our last night in Portland. She made the experience enjoyable. She did as much as she could. Just not sure why the hotel couldn’t fix the A/C in the rooms with KNOWN issues.

Reviewed on Jul 8, 2026

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More About Flying To Great Diamond Island from St. Louis

Route Information for Flights from St. Louis to Great Diamond Island

Origin Airport IATA Code
STL
Destination Airport IATA Code
PWM
Distance
Direct Flight Airlines
Earliest Flight Arrival
Latest Flight Arrival

St. Louis to Great Diamond Island

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Fare, taxes & fees: Fares include all taxes and fees, except baggage fees. Rates shown reflect fares found by other Orbitz users over the past 7 days. Due to rapidly changing airline prices & seat availability, these fares may no longer be available.

Refunds/changes/cancellations: Itinerary changes, if permitted for the fare, will have a $30 service fee charged by Orbitz. Additional airline charges may apply.

Other conditions: Schedules, fares and rules are subject to change without notice. Seats are limited and may not be available on all flights/dates or in all markets. Lower fares may be available. Fares will not be honored retroactively or in exchange for any wholly/partially unused ticket. Tickets are non-transferable and non-refundable. Fare rules are provided for the selected itinerary before booking.