Hidden Flight Fees 2026: What You Really Pay on Skyscanner, Momondo & Kayak

Hidden Flight Fees in 2026: What You Actually Pay on Skyscanner, Momondo, and Kayak

You found a flight for 2,000 NOK. At checkout, it was 2,800 NOK. What happened?

This isn't a glitch — it's how most flight comparison sites are built to work. The number you see on the results page is almost never the number you pay. Here's exactly where the gap comes from, and how to spot it before you click "Book."

Why the headline price and the checkout price differ

Comparison engines like Skyscanner, Momondo, and Kayak don't sell tickets themselves. They show offers from airlines and third-party travel agencies (OTAs), then send you onward to complete the booking. The price they display is usually the base fare only — before the extras that OTAs add once you're on their site.

That's not necessarily dishonest, but it means the price you're comparing on the results page often isn't apples-to-apples.

Where the fees actually hide

OTA service fees Many OTAs add a booking or service fee at checkout — sometimes labeled clearly, sometimes folded quietly into the final total. This alone can add 5–15% to the price you first saw.

Bags added by default Some results are built on the cheapest fare class, which often excludes checked luggage. If you need a bag, it gets added at checkout — and on some sites, a default bag is pre-selected and easy to miss unchecking.

Seat selection Basic fares increasingly assign seats randomly unless you pay extra. If you want to sit with a travel companion or pick anything other than a middle seat, expect an add-on charge.

Currency conversion markup Booking through an OTA based in another country can mean your card issuer converts the price at a worse rate than the displayed currency suggests — a cost that never shows up on the comparison page at all.

"Self-transfer" itineraries On multi-airline connections, some engines show a cheap combined fare that isn't actually protected as one ticket. If your first flight is delayed and you miss the connection, you may not be rebooked or refunded — a real risk that has nothing to do with price, but affects the total cost of things going wrong.

What we found testing real routes

Across a 100-route test comparing checkout totals (not headline prices) on Skyscanner, Momondo, Kayak, and Voyara, the gap between headline and final price ranged from 3% to 25%, most often driven by exactly the factors above — OTA fees layered onto an already-cheap base fare.

One concrete example: a Skyscanner result for an Oslo–Bangkok flight showed 4,820 NOK on the results page. At checkout, after the OTA's service fee and standard bag, the total was 5,690 NOK — a jump of over 850 NOK that never appeared anywhere on the comparison page itself.

A 5-point checklist before you click "Book"

1. Open the final checkout page before comparing prices across sites. The results-page number is a starting point, not the answer.
2. Check if a bag is already included — or already added. Both happen, and neither is obvious at a glance.
3. Look for the airline's name in the URL at checkout. If you're being redirected through an unfamiliar OTA rather than the airline directly, read the fine print on refund and change policies.
4. Compare the currency your card will actually be charged in, not just the currency displayed on the results page.
5. If it's a multi-airline itinerary, search "self-transfer" plus the airline names to check whether you're protected if a connection is missed.

The simplest fix

Compare all-in checkout prices, not headline prices, across at least two sources before booking. If two independent checks land within a few percent of each other, you can book with confidence. If one source is dramatically cheaper than another for the identical flight, that gap is almost always sitting in fees you haven't seen yet — go find them before you pay.

See the real all-in price, no surprises at checkout, on Voyara →

Related: Skyscanner vs Momondo vs Kayak: An Honest 2026 Comparison