Few subjects attract as much folklore as airfares. “Buy on Tuesday at 3am.” “Search in incognito mode.” Test these against actual data and most turn out weak or flip from year to year.
What genuinely saves money is simpler: when you fly matters far more than when you buy.
1. What actually moves the price. Your departure day, not your purchase day — when you fly matters far more than when you buy. Booking timing is about how far out you are, not a magic weekday.
2. What people miss. The displayed price is not the price — compare on total cost including bags and fees or the ranking flips at checkout.
3. When it goes wrong. The US Department of Transportation fixes numeric thresholds at which airlines must refund automatically, without the passenger asking — but that is a US rule, and this article does not claim it covers flights to and from other countries.
1. Testing the myths
| Claim | Reality |
| “Tuesday is the cheapest day to buy” | Weakly supported. Studies disagree — the same source has named Sunday one year and Friday the next |
| “Incognito mode lowers prices” | Largely negligible. Prices move with seat inventory and demand |
| “Last minute is always cheaper” | A gamble — off-season deals exist, but peak season spikes |
| “Earlier is always cheaper” | Book too early and only higher initial fare buckets are open |
| “Changing your departure day helps” | This one is real |
The Tuesday story has roots: airlines once released fare sales early in the week. But pricing is now algorithmic and continuous, which has flattened that pattern.
2. What actually moves the price
| Factor | Expensive / cheaper |
| Departure day | Fri–Sun, especially Friday evening / Tue and Wed, often Saturday too |
| Departure time | Mid-morning and after work / very early or late night |
| Season | Summer peak, holidays / shoulder and low season |
| Flexibility | Fixed dates / ±3 days |
The logic is avoiding both business and weekend demand. Business travellers leave Monday and return Friday; weekend travellers leave Friday evening. Tuesday and Wednesday fall in the gap. Shifting your departure by three days beats obsessing over purchase day.
3. When to book — measured in weeks out
| Trip type | Suggested booking window |
| Domestic | 1–3 months ahead |
| International, off-peak | 2–6 months ahead |
| International, peak or holidays | 6–10 months ahead |
| Fixed-date events | Prioritise securing the seat over price |
Peak season is the exception: when demand is certain, waiting costs money. “A deal will appear” rarely works in July and August.
4. Searching properly
- Set price alerts — more accurate and less effort than checking daily.
- Search by whole month — calendar views show the cheapest dates, and one day often swings the fare noticeably.
- Widen your airports — big cities have several, and a nearby city plus ground transport can undercut them.
- Compare round-trip against two one-ways, potentially on different airlines.
- Don't dismiss connections — one stop often cuts the fare sharply. Just check layover time and baggage transfer.
5. Compare totals, not headline fares
| Item | What to check |
| Checked bag | Included? Weight? Adding later costs far more |
| Cabin bag | Basic fares may allow only a small personal item |
| Seat selection | Free or paid |
| Payment fee | Some sellers charge for card payment |
| Changes and refunds | Cheap fares are often non-changeable and non-refundable |
| Airport location | Outlying airports add transfer cost and time |
Those last two matter most. A fare that's cheaper by the price of a return airport bus, arriving at 2am, isn't really cheaper. Compare door to door.
6. Airline direct vs booking sites
| Airline website | Changes and disruptions handled directly and faster, reliable mileage / sometimes slightly pricier |
| Booking site | Easy comparison, promo codes / an extra party when something goes wrong |
When prices are close, book direct — the difference in handling a cancellation is stark. If you use an agency, check its change policy and support channels first.
7. One more thing at checkout
If a foreign airline or booking site offers to charge you in your home currency, decline. That's dynamic currency conversion, and it typically adds 3–8%. Always choose the local currency — see cutting overseas payment fees.
Checklist
- Decide your date range first (±3 days opens far more options)
- Use month-view search to find cheap date bands
- Set a price alert
- Include Tue/Wed departures and early or late flights
- Compare finalists on total cost including bags and transfers
- If close, book direct
- Pay in local currency
- Verify name spelling immediately — corrections cost money
Delays and cancellations trigger an automatic refund — under US rules
Buying cheaply matters less than getting your money back when the trip falls apart. The US Department of Transportation sets numeric thresholds at which an airline must refund you without being asked.
| Situation | Automatic refund threshold | Note |
|---|---|---|
| Flight, domestic | 3 hours or more departure or arrival delay | cancellations too |
| Flight, international | 6 hours or more departure or arrival delay | cancellations too |
| Baggage, domestic | more than 12 hours after arrival | a mishandled-baggage report must be filed |
| Baggage, international | 15 hours (flights up to 12h) / 30 hours (over 12h) | same |
The deadlines are fixed too — 7 business days for credit card payments, 20 for cash or cheque. And it must come back the way you paid, not as a voucher or miles. That is the point of the rule.
The necessary caveat. This is a US Department of Transportation rule, and it does not automatically cover flights touching Korea. The page does not set out which routes or carriers it reaches, so this article stops at “the US rules contain these numbers” (see below).
It is still useful — remembering “3 hours” and “6 hours” when booking a US route gives you a basis for what to ask the airline for when a delay hits. We could not find an equivalent Korean agency standard this time.
Questions that remain
Should I wait for the price to drop?
Reasonable off-season with flexible dates. For peak periods or fixed dates, waiting usually costs more.
Connections are much cheaper — is that fine?
Check for at least two hours (more internationally) and whether bags transfer through. Separately ticketed flights don't protect you if the first leg is late.
Are miles worth using?
Generally best on long-haul or premium cabins. Short economy redemptions usually waste value.
Airfare isn't a game of when you buy — it's when you fly. If you can move your dates by three days, that's the biggest discount available.
Do the US rules apply to Korean airlines?
This article does not claim they do. The DOT page carries no breakdown of scope by route or carrier nationality, so we could not confirm it. On a US route, asking the airline directly whether a DOT automatic refund applies is the fastest answer.
Are there fees for paying in a foreign currency?
Yes. A network fee (MasterCard 1.0% / Visa 1.0–1.1% / Amex 1.4%) plus a card issuer's overseas-use fee (0–0.35%). The layers are set out in our overseas payment fees article. Decline if asked to pay in Korean won — that is one extra currency conversion.
Airfare isn't a game of when you buy — it's when you fly. If you can move your dates by three days, that's the strongest discount available.
Sources
- US Department of Transportation — agency source — “Refunds” (checked 30 July 2026). Source for the 3-hour domestic and 6-hour international automatic refund thresholds, 12-hour domestic and 15- or 30-hour international baggage thresholds, 7 and 20 business day deadlines, and the mishandled-baggage report requirement.
- US Consumer Financial Protection Bureau — “What is a foreign transaction fee?” (checked 30 July 2026). The two layers of overseas payment cost are set out in our overseas payment fees article, verified against this definition and a card issuer's disclosure. The issuer disclosure is a private disclosure.
- The rest of this article's advice has no agency source. It gathers commonly used methods, not anything a public body has verified.
Where to check further
- Which refund rules apply to your own ticket. The automatic-refund thresholds here are US Department of Transportation rules, and the page does not set out which routes or carriers they reach, so no wider claim is made. For Korean itineraries, the Korea Consumer Agency's dispute resolution standards set out delay and cancellation remedies.
- Whether “Tuesdays are cheaper” holds. No government fare statistics could be found, so this article asserts nothing. If you want to know, track one route yourself over several weeks — that beats any article on the subject.
- Fare rules and fees by airline. Change and refund terms differ by fare class, even on the same flight with the same carrier. Open that fare's rules page before paying.
As of July 2026. The automatic refund thresholds come from the US Department of Transportation's page; the rest of the advice has no agency source. This is general information and does not endorse specific airlines or agencies. Fare rules and fees vary — check the conditions before booking. Lodging is in our hotel booking article, packing in the packing guide, and trouble abroad in the travel emergency article.
