Best Flights starting from $463
from$463economy
Philadelphia (Any)
Tue, Dec 1
Roundtrip
St Louis (STL)
Sat, Dec 12
from$463economy
Philadelphia (Any)
Thu, Dec 3
Roundtrip
St Louis (STL)
Mon, Dec 14
from$463economy
Philadelphia (Any)
Fri, Dec 4
Roundtrip
St Louis (STL)
Tue, Dec 15
from$463economy
Philadelphia (Any)
Sat, Dec 5
Roundtrip
St Louis (STL)
Wed, Dec 16
from$474economy
Philadelphia (Any)
Wed, Dec 2
Roundtrip
St Louis (STL)
Sun, Dec 13
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Other Destinations
Philadelphia (Any) to Houston (Any) in December from $50
From $50
Philadelphia (Any) to Chicago (Any) in December from $54
From $54
Philadelphia (Any) to Denver (Any) in December from $54
From $54
Philadelphia (Any) to Dallas (Any) in December from $54
From $54
Philadelphia (Any) to Detroit (DTW) in December from $59
From $59
Philadelphia (Any) to Miami (Any) in December from $67
From $67
Flights from Other Cities
Salt Lake City (SLC) to St Louis (STL) in December from $127
From $127
Minneapolis (MSP) to St Louis (STL) in December from $208
From $208
Sacramento (SMF) to St Louis (STL) in December from $305
From $305
Madison (MSN) to St Louis (STL) in December from $352
From $352
Charleston (CRW) to St Louis (STL) in December from $465
From $465
Sacramento (SMF) to St Louis (STL) in January from $255
From $255
✈️ Flight Guide: Philadelphia (Any) → St Louis (STL)
Complete travel information for your December journey
Departing from Philadelphia (Any) FAQs
To find the cheapest economy flights from St. Louis Lambert International Airport (STL), use fare comparison tools, set price alerts, and search flexible dates using a low-fare calendar. Consider flying mid-week (Tuesdays/Wednesdays) and booking 6–10 weeks in advance for domestic economy routes. Check low-cost carriers like Southwest and Frontier for unbundled fares and watch for seasonal sales.
From St. Louis Lambert International Airport (STL) you can access major hubs and popular destinations such as Chicago, Kansas City, Nashville, Indianapolis, Memphis, Dallas, Atlanta and Orlando. These flight corridors often have competitive economy fares and multiple daily flights, making them ideal for budget travelers and connections across the U.S.
Yes. In January and February you’ll often find the lowest domestic economy fares after the holiday surge, while June through August are peak summer months with higher prices. November (except Thanksgiving week) and late September are often shoulder seasons offering discounted economy seats for both domestic and leisure routes. Use monthly fare calendars to time purchases.
Baggage rules vary by airline: many basic economy fares do not include checked bags and may restrict carry-on items to personal item only. Always check the specific airline policy before booking at St. Louis Lambert International Airport (STL) and factor baggage fees into the total cost to compare true economy prices. Consider a credit card or bundled fare that includes a checked bag if you need more luggage.
For domestic economy departures at St. Louis Lambert International Airport (STL), arrive at least 90 minutes to 2 hours before scheduled departure to allow for parking, security (TSA), and boarding. Peak travel times (holiday mornings, major events) may require earlier arrival; consider checking real-time security wait times through the airport before you leave.
For beach trips from St. Louis Lambert International Airport (STL), consider booking travel in May, September, or early October for lower economy fares and pleasant weather. These shoulder-season months often provide a balance of lower prices and reliable conditions, while peak summer (June–August) typically commands higher rates.
Arriving at St Louis (STL) FAQs
Cheapest Economy Fare (ECN) typically refers to the lowest-priced economy class ticket on a given route, often with restrictions such as limited or no seat selection, reduced or no baggage allowance, and stricter change/cancellation policies. Travelers should read fare rules carefully to confirm what is included and consider added fees when comparing total trip costs.
Cheapest Economy Fare (ECN) arrivals frequently target high-competition airports and major cities such as New York, Miami, Los Angeles, Las Vegas, Orlando, and Dallas. Budget-conscious travelers also find low ECN fares to tourist hubs like Nashville and Denver depending on seasonality and carrier competition.
Yes, ECN arrival prices vary by month. January and February often have the lowest arrival fares in ECN due to lower travel demand, while June–August and December holidays see elevated fares. Shoulder months like September and November can offer good ECN deals for travelers seeking lower prices.
To avoid unexpected baggage or seat fees with ECN arrivals, review the fare rules before purchasing, add necessary baggage at booking time (often cheaper than at the airport), and consider a slightly higher fare class if it includes luggage. Keep an itemized record of total cost so you compare true value between ECN and bundled economy options.
During peak events or festivals in a destination, book ECN arrivals early and verify change/cancellation terms because prices rise quickly near event dates. For example, if traveling for a May festival, lock fares 8–12 weeks out and monitor fare alerts for drop opportunities. Consider flexible tickets or refundable options if event dates are uncertain.
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Events & Festivals Impacting STL Fares — Plan for Cheapest Economy
Major events such as the St. Louis Cardinals home stand, Taste of St. Louis (summer months), and regional music festivals can raise demand and economy fares. Similarly, events in arrival cities (e.g., New York Fashion Week in September or Ultra Music Festival in March) can spike ECN arrival prices. If you must travel for an event, book early and consider arriving a day early or staying a day later to reduce cost. CTA: Check event calendars when planning your trip and book accordingly to avoid inflated economy fares.
Best Time to Fly from STL — Optimize for Cheapest Economy (ECN)
Generally, the best time to fly on the cheapest economy fares from St. Louis Lambert International Airport (STL) is mid-week during shoulder seasons—late January through March (excluding spring break) and September through early November. Book domestic economy tickets about 1.5–3 months in advance for the best balance of price and availability; for peak summer and holiday travel, book 3–6 months ahead. Use fare alerts and low-fare calendars to spot sudden drops and flash sales.
Direct vs Connecting Flights — Cheapest Economy Tradeoffs from STL
Connecting flights can offer substantial savings in the cheapest economy class at the cost of longer travel time and potential missed-connection risk. Direct flights are more convenient and reduce total travel time but often command a premium. If maximizing savings from St. Louis Lambert International Airport (STL) is your priority, search one-stop ECN itineraries through hub airports like Dallas-Fort Worth or Atlanta. Balance savings against potential disruption risk and allow ample connection time, especially on separate tickets.
Airline Comparison for STL — Economy & Cheapest Fare (ECN) Options
Southwest: Often the best value for economy travelers out of St. Louis Lambert International Airport (STL) due to two free checked bags and no change fees, though base fares may be slightly higher. Delta/American/United: Offer more hub connectivity and competitive sale fares; basic economy usually restricts seat selection and carry-on policies. Frontier/Spirit: Tend to have the lowest headline ECN-style fares but charge for nearly every add-on (seat selection, carry-on, checked bags), so compare total price. CTA: Compare all-in pricing, not just headline fares, to find the true cheapest economy option from STL.
Seasonal Travel Tips — Save on Economy Flights from STL & ECN Arrivals
Flight Times and Schedules — STL Departures to Major ECN Destinations
Cheap Flights Guide: STL to ECN — Strategies & Tools
To find cheap economy flights from St. Louis Lambert International Airport (STL) with ECN-style arrivals, combine flexible-date searches, price alerts, and multi-airline comparisons. Use the low-fare calendar to find the cheapest days to fly, and sign up for OTA and airline newsletters to catch flash sales. Consider booking one-ways with different carriers and check alternate nearby airports like Chicago or Kansas City if it lowers total trip cost. CTA: Start a 30-day fare watch to capture the best economy deals.