$54 Cheap flight deals from Carlsbad (SAN) to Boulder (DEN)

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This Weekend's Flight Deals from Carlsbad to Boulder

This weekend's flight prices found within the past 7 days, for the period specified. Prices and availability are subject to change. Additional terms apply.

Sun, May 11 - Sun, May 18
SAN
San Diego Intl.
DEN
Denver Intl.
$217 Roundtrip, found 2 hours ago
$217
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Sun, May 11 from San Diego Intl. to Denver Intl., returning Sun, May 18, priced at $217 found 2 hours ago
Sat, May 10 - Mon, May 12
CLD
McClellan-Palomar
DEN
Denver Intl.
$361 Roundtrip, found 3 days ago
$361
Roundtrip
found 3 days ago
Select American Airlines flight, departing Sat, May 10 from McClellan-Palomar to Denver Intl., returning Mon, May 12, priced at $361 found 3 days ago

Airfares from $54 One Way, $108 Round Trip from Carlsbad to Boulder

Prices starting at $108 for return flights and $54 for one-way flights to Boulder were the cheapest prices found within the past 7 days, for the period specified. Prices and availability are subject to change. Additional terms apply.

Sat, May 31 - Sat, Jun 7
SAN
San Diego
DEN
Denver
$108 Roundtrip, found 3 hours ago
$108
Roundtrip
found 3 hours ago
Select Frontier Airlines flight, departing Sat, May 31 from San Diego to Denver, returning Sat, Jun 7, priced at $108 found 3 hours ago
Sat, May 31 - Sat, Jun 7
SAN
San Diego
DEN
Denver
$110 Roundtrip, found 3 hours ago
$110
Roundtrip
found 3 hours ago
Select Frontier Airlines flight, departing Sat, May 31 from San Diego to Denver, returning Sat, Jun 7, priced at $110 found 3 hours ago
Tue, May 20 - Sat, May 24
SAN
San Diego
DEN
Denver
$113 Roundtrip, found 1 hour ago
$113
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Tue, May 20 from San Diego to Denver, returning Sat, May 24, priced at $113 found 1 hour ago
Wed, May 21 - Sat, May 24
SAN
San Diego
DEN
Denver
$115 Roundtrip, found 1 hour ago
$115
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Wed, May 21 from San Diego to Denver, returning Sat, May 24, priced at $115 found 1 hour ago
Wed, Oct 8 - Tue, Oct 14
SAN
San Diego
DEN
Denver
$177 Roundtrip, found 4 hours ago
$177
Roundtrip
found 4 hours ago
Select Alaska Airlines flight, departing Wed, Oct 8 from San Diego to Denver, returning Tue, Oct 14, priced at $177 found 4 hours ago

Boulder economy flight packages

Price found within the past 48 hours. Click for updated prices.
Holiday Inn Denver East by IHG
3.5-star property

Holiday Inn Denver East by IHG

7.2/10 Good! (1,135 reviews)

Jun 28 - Jun 30

2 night stay

San Diego (SAN) to Denver (DEN)

Frontier Airlines • Roundtrip • Coach
per person
found 1 day ago
We had a great overnight stay at this property. 1/2 hood, 1/2 not - but easy and comfortable. Parking isn’t free which sucks - $15/day - that parked sucked considering we weren’t in the city. But staff was nice. No free breakfast. Balcony room was great on the top floor!

Reviewed on Apr 24, 2025

The Maven Hotel at Dairy Block
4.0-star property

The Maven Hotel at Dairy Block

9.4/10 Exceptional! (1,075 reviews)

Jun 13 - Jun 15

2 night stay

San Diego (SAN) to Denver (DEN)

Frontier Airlines • Roundtrip • Coach
per person
found 13 hours ago
Great vibe. Unique.

Reviewed on Oct 27, 2024

The Crawford Hotel
5.0-star property

The Crawford Hotel

9.2/10 Wonderful! (1,008 reviews)

Jun 13 - Jun 15

2 night stay

San Diego (SAN) to Denver (DEN)

Frontier Airlines • Roundtrip • Coach
per person
found 13 hours ago
Great hotel with incredible turn of the century charm. Located within a historic train station the hotel embraces its past and makes staying an experience.

Reviewed on May 6, 2025

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More About Flying To Boulder from Carlsbad

Route Information for Flights from Carlsbad to Boulder

Origin Airport IATA Code
SAN
Destination Airport IATA Code
DEN
Distance
Direct Flight Airlines
Earliest Flight Arrival
Latest Flight Arrival

Carlsbad to Boulder

Grab great fares on Carlsbad to Boulder flights with Orbitz, your #1 source for discount international and domestic air tickets. Our cutting-edge mobile tools and great online search functionality make booking your next budget trip a breeze.

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Frequently asked questions

Are there non-stop flights from Carlsbad to Boulder?
Yes, if you’re heading from San Diego, CA (SAN-San Diego Intl.) to Denver Intl. Airport (DEN), you’ll only have one flight number to keep in mind. There are 3 airlines that offer nonstop services to pick from. Here are a few of the best:

  • Southwest Airlines
  • United Airlines
  • Frontier Airlines

What is the shortest flight from Carlsbad to Boulder?
If conditions are good and all goes according to plan, you could be flying into DIA airport from San Diego, CA (SAN-San Diego Intl.) in as little as 2 hours and 15 minutes. With such a fast flight time, consider traveling with hand luggage only.
What airlines fly from Carlsbad to Boulder most frequently?
Southwest Airlines (WN) offers 178 flights every month between San Diego, CA (SAN-San Diego Intl.) to Denver, CO (DEN-Denver Intl.). Your next big adventure is just a few clicks away. Alternatively, reserve your favorite window (or aisle) seat with United Airlines (UA). You’ll have 152 monthly flights between Carlsbad and Boulder to select from with this carrier.
What is the cheapest day of the week to fly?
Consider flying out early in the week to save on your airfare. Orbitz data from 2021 shows that Monday is the cheapest day to depart, followed by Tuesday. Saturday showed the highest average ticket prices likely because many travelers prefer to start their vacation on a weekend.
What is the cheapest month to fly?
We won’t keep you guessing, according to Orbitz data from 2021, the cheapest month to fly is February. Perfect for those who need a weekend getaway, or just a break from it all in the shortest month of the year. Be aware that the most expensive time to fly is during the height of summer in July, and in the holiday month of December.*According to flight demand on Orbitz.com from January to December 2021. Savings are subject to change based on departure location, date and destination.

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.