Airline sale calendar 2025: When to find the cheapest flights

• January emerges as the cheapest month to fly with post-holiday demand drops saving travelers ~$125 compared to November peak pricing

• September delivers the ultimate bargain with shoulder season fares often 50%+ below summer levels — Europe roundtrips under $500 when they cost $1000+ in July

• March offers the sweet spot for booking summer travel 4-6 months ahead when international fares are at their lowest before spring competition

• May provides exceptional value for Europe travel with warm weather and pre-peak crowds, while Asia offers comfortable temperatures before monsoon season

• July ranks as the most expensive month for flights with peak summer demand, though Southwest breaks industry pricing discipline with aggressive promotions

• November concentrates the year's biggest travel deals around Black Friday and Travel Tuesday, making it the prime booking window for 2026 travel

Finding cheap flights requires understanding both when to travel (for the lowest fares) and when to book (for the best deals). SimplyCodes analysis reveals the optimal timing for both immediate travel bargains and advance booking opportunities throughout 2025.

The cheapest vs. most expensive months to fly

Understanding airline pricing cycles helps you time both immediate travel and advance bookings for maximum savings.

Absolute cheapest travel months

January leads as the cheapest month to actually fly, with post-holiday demand drops creating savings averaging $125 compared to peak November pricing. Airlines desperately fill planes during this traditionally slow period.

February continues the low-cost trend as the year's quietest travel month, offering bargain rates especially for international destinations still in off-season.

September delivers exceptional shoulder season value with fares often 50%+ below summer levels. Europe flights that cost $1000+ in July frequently drop under $500 in September.

Most expensive travel periods

July consistently ranks as the year's most expensive month, with peak summer demand driving prices to annual highs across most routes.

December 16-January 1 creates the year's second-most expensive period due to concentrated holiday travel demand.

March 8-24 sees spring break price spikes, particularly to warm-weather destinations and ski resorts.

Airline promotional patterns by month

Our analysis of airline promo code releases from Delta, Southwest, United, and Alaska Airlines from September 2023 through July 2025 reveals distinct promotional calendars that savvy travelers can leverage for maximum savings.

Month-by-month flight cost analysis for 2025

January 2025: Annual price low point

Travel costs: Cheapest month of the year (average $125 below peak pricing) Best for: Europe/Asia bargains, domestic winter travel Promotional support: Strong (Alaska: 9 codes, Delta: 4 codes)

January creates a perfect storm for cheap flights. Post-holiday travel demand plummets as consumers recover from December spending, while airlines face their emptiest planes of the year. This combination produces genuine bargains across most routes.

International flights to Europe and Asia hit annual lows due to winter off-season demand. For example, flights to Italy in January can cost 60%+ less than summer rates because tourism drops dramatically in winter months.

Specific cost examples:

• Europe roundtrips: Often $300-500 vs. $800-1200 in summer

• Domestic routes: Winter weather destinations see major price drops

• Asia flights: Pre-Lunar New Year pricing offers substantial savings

Why it's cheap: School schedules, weather concerns, and post-holiday financial recovery create minimal demand while airlines have maximum capacity to fill.

February 2025: Continued winter bargains

Travel costs: Second cheapest month annually Best for: Warm weather escapes, Europe city breaks Promotional support: Moderate (balanced 2-4 codes across carriers)

February extends January's low pricing with the added benefit of being the year's absolutely quietest travel month. Airlines see their lowest passenger volumes, creating exceptional bargains for flexible travelers.

The major exception comes around Presidents' Day weekend (February 15-17) when ski destinations and warm-weather escapes see temporary price spikes. However, mid-February offers some of the year's best deals.

Specific cost examples:

• Caribbean: Winter escape pricing remains reasonable before spring break demand

• Europe: Cities like Rome, Paris offer hotel+flight packages at annual lows

• Domestic: Avoiding holiday weekend creates substantial savings

Booking opportunity: Use February's slow period to book May-August international travel when advance purchase pricing is most favorable.

March 2025: Spring break price surge begins

Travel costs: Expensive for immediate travel, optimal for summer bookings Best for: Booking ahead, early March shoulder season Promotional support: Peak activity (United: 5 codes, Delta: 6 codes)

March presents a split personality for flight costs. Immediate travel faces spring break price spikes, particularly mid-March when schools break. However, March represents the optimal booking window for summer travel.

Early March (first two weeks) maintains some late-winter pricing before spring break demand intensifies. Late March sees significant price increases to popular spring break destinations.

Specific cost examples:

• Florida/Mexico: 200-300% price increases during peak spring break weeks

• Europe summer bookings: 4-6 month advance window offers optimal pricing

• Domestic spring break routes: Avoid March 8-24 for immediate travel

Strategic value: Despite high immediate travel costs, March's promotional activity makes it ideal for locking in summer Europe flights before prices climb.

April 2025: Shoulder season sweet spot

Travel costs: Moderate, excellent value for Europe Best for: Europe shoulder season, spring domestic travel Promotional support: Consistent (4 codes across all carriers)

April offers exceptional value for actual travel, balancing pleasant spring weather with pre-peak pricing. Excluding Easter week (April 13-20), April provides affordable access to Europe's spring season.

Transatlantic fares remain significantly below summer levels while weather improves from deep winter. Europe experiences spring blooms and mild temperatures without summer crowds.

Specific cost examples:

• Europe flights: Still 30-40% below peak summer pricing

• Domestic routes: Spring weather destinations offer good value

• Asia travel: Comfortable temperatures before summer heat

Value proposition: April delivers premium travel experiences at shoulder season prices, making it one of the year's best cost-to-experience ratios.

May 2025: Premium shoulder season

Travel costs: Moderate, rising toward summer levels Best for: Europe prime time, Asia before monsoons Promotional support: Limited (1-3 codes per carrier)

May represents the last month of true shoulder season pricing before summer premiums take effect. Early May offers better value than late May as summer booking competition intensifies.

Europe enjoys ideal weather without peak crowds, while Asia offers comfortable temperatures before monsoon seasons. Airlines begin reducing promotional activity as natural demand increases.

Specific cost examples:

• Europe: Warm weather with pricing 20-30% below July/August levels

• Asia: Pre-monsoon timing offers excellent weather-to-price ratios

• Domestic: Spring travel maintains reasonable pricing before summer peaks

Strategic timing: Book May travel by March to capture advance purchase pricing before seasonal increases.

June 2025: Summer pricing begins

Travel costs: Expensive, peak season pricing starts Best for: Early June travel, booking fall trips Promotional support: Minimal (1-4 codes per carrier)

June marks the beginning of peak summer pricing as schools release students for vacation. Early June (first two weeks) maintains some pricing advantages before full family travel season begins.

Mid-to-late June sees significant price increases as summer travel demand reaches full strength. Airlines reduce promotional activity knowing seats will sell at higher prices.

Specific cost examples:

• Europe: Pricing jumps 40-60% from May levels by mid-June

• Domestic family routes: School vacation timing drives major increases

• International: Long-haul routes see substantial premium pricing

Cost management: Target early June for travel, late June for booking fall trips at advance purchase rates.

July 2025: Peak pricing season

Travel costs: Most expensive month for most routes Best for: Southwest network routes (due to promotions) Promotional support: Southwest dominates (15 codes), others minimal

July consistently ranks as the year's most expensive travel month due to peak summer demand. Family vacation timing creates the highest passenger volumes and corresponding price peaks.

However, Southwest's aggressive promotional strategy (15 codes in 2024) creates unique value within their route network, bucking industry pricing trends during peak season.

Specific cost examples:

• Europe roundtrips: Often $1000-1500+ (2-3x January pricing)

• Domestic family routes: Peak pricing with limited availability

• International: Premium pricing across most long-haul destinations

Value strategy: Focus on Southwest promotions for domestic routes, consider mid-week departures for slight relief from weekend premiums.

August 2025: Late summer relief begins

Travel costs: High early month, declining late August Best for: Late August bargains, European late summer Promotional support: Southwest (6 codes), Alaska (5 codes)

August spans expensive early summer and more reasonable late-summer pricing. The key transition occurs around August 20-25 when family travel winds down for school preparation.

Late August often sees dramatic price reductions as airlines try to fill remaining summer inventory before fall schedules begin.

Specific cost examples:

• Late August Europe: 30-40% below peak July pricing

• Domestic routes: Significant drops final week as families prepare for school

• International: Shoulder season pricing begins for many destinations

Timing strategy: Target late August for immediate travel savings, early August for fall advance bookings.

September 2025: Ultimate travel bargain month

Travel costs: Cheapest shoulder season pricing (50%+ below summer) Best for: Europe harvest season, domestic fall travel Promotional support: Strong (Delta: 7 codes, Southwest: 6 codes)

September consistently delivers the year's best travel value, earning the industry nickname "Sale-tember." Demand plummets after summer vacations end while weather remains excellent across most destinations.

Europe offers harvest season appeal with dramatically reduced pricing, while domestic destinations provide comfortable fall weather at substantial savings.

Specific cost examples:

• Europe roundtrips: Often $300-600 (vs. $1000+ in July)

• Domestic routes: Fall weather destinations at 40-50% summer discounts

• Asia: Post-monsoon excellent weather with reduced pricing

Value advantage: September provides premium travel experiences at budget prices, making it ideal for flexible travelers seeking maximum value.

October 2025: Fall value continuation

Travel costs: Continued shoulder season benefits Best for: Fall foliage, Europe autumn weather Promotional support: Moderate (3-4 codes across carriers)

October extends September's value proposition while adding spectacular fall foliage opportunities in North America. Columbus Day weekend (October 13) creates minor price spikes but overall pricing remains favorable.

Europe continues offering excellent weather without summer crowds, while domestic fall destinations provide peak autumn colors at reasonable prices.

Specific cost examples:

• New England foliage routes: Peak autumn colors without summer premiums

• Europe: Continued pleasant weather at off-season pricing

• Domestic routes: Fall weather appeal with moderate pricing

November 2025: Booking bonanza month

Travel costs: Early month reasonable, Thanksgiving week expensive Best for: Black Friday deal hunting for 2026 travel Promotional support: Peak activity (Alaska: 11 codes across carriers)

November splits between reasonable early-month travel pricing and expensive Thanksgiving week premiums. However, November's primary value lies in Black Friday and Travel Tuesday promotional opportunities for future travel.

Travel Tuesday (December 2, 2025) historically offers the year's most aggressive promotional activity across all carriers.

Specific cost examples:

• Early November travel: Continued fall shoulder season benefits

• Thanksgiving week: Premium pricing rivaling summer levels

• Advance bookings: Black Friday deals for spring/summer 2026 travel

Strategic focus: Use November for booking 2026 travel rather than immediate travel due to Thanksgiving premiums.

December 2025: Holiday split pricing

Travel costs: Cheap early month, very expensive December 16-January 1 Best for: Early December travel, Christmas market trips Promotional support: Balanced (3-5 codes across carriers)

December offers the year's starkest pricing contrast. December 1-15 ranks among the cheapest travel periods, while December 16-January 1 creates some of the year's highest prices.

Early December travel provides excellent value for experiencing European Christmas markets and holiday atmosphere before premium holiday pricing begins.

Specific cost examples:

• Early December: Among year's cheapest travel periods

• Christmas week: Premium pricing often 200-300% above early December

• European Christmas markets: Early season offers atmosphere with reasonable pricing

Timing critical: December 15 represents the cutoff between bargain and premium holiday pricing.

How to save money on flights in 2025

Cheapest months to actually fly

1. January: Post-holiday demand drop creates annual price lows

2. February: Quietest travel month with exceptional bargains

3. September: Shoulder season excellence with 50%+ summer savings

4. Early December: Pre-holiday bargains before premium pricing

Most expensive months to avoid

1. July: Peak summer demand creates annual price highs

2. December 16-January 1: Holiday premium pricing

3. March 8-24: Spring break price surges

4. Late June: Summer family travel pricing begins

Best booking windows by travel period

• Spring travel (Mar-May): Book in January-February

• Summer travel (Jun-Aug): Book in March-April before promotional drought

• Fall travel (Sep-Nov): Book in August-September

• Holiday travel (Dec-Jan): Book during November's Black Friday concentration

International vs. domestic cost patterns

Europe travel optimization:

• Cheapest travel: January, September (50-60% below summer)

• Best booking windows: January-March for summer travel

• Shoulder season sweet spots: April-May, September-October

Asia travel strategies:

• Optimal timing: January-February, May (pre-monsoon), September-October

• Monsoon avoidance: June-August often problematic for weather

• Advance booking: 3-5 months optimal for most Asia routes

Domestic cost management:

• Winter bargains: January-February for warm weather destinations

• Summer avoidance: July peak pricing, late August relief

• Fall value: September-October for comfortable weather nationwide

The key to airline savings in 2025 is understanding that the cheapest travel months (January, September, early December) offer genuine cost advantages due to demand patterns, while promotional activity helps optimize booking timing for future travel during more expensive periods.

How we get this data: Pricing trends sourced from industry analysis and historical booking data. Promotional activity tracked through our comprehensive airline monitoring system.

Looking for current airline deals? Find verified airline promo codes here