Probably is due to a fuel surcharge. Might be listed as an airline "YQ surcharge". The money goes to the airline. In one case the "taxes and fees or the fare includes the surcharge and in the other case they don't.

Here are the details for a ticket from LAX to Frankfurt on Air India.

Is the total "fare" without taxes= $223+$197= $420?
Or is the fare the $420 plus the $150 surcharge?

Fare (A1): AI LAXFRA MEU12H fare (rules) $223.00
Fare (A2): AI FRALAX VEU12H fare (rules) $197.00
Tax: US September 11th Security Fee $2.50
Tax: US International Departure Tax $15.40
Tax: US Passenger Facility Charge $4.50
Tax: US International Arrival Tax $15.40
Tax: German Passenger Service Charge €20.73
Tax: German Airport Security Tax €6.55
Tax: US Customs Fee $5.50
Tax: US Immigration Fee $7.00
Tax: USDA APHIS Fee $5.00
Tax: AI YQ surcharge $150.00

-----------------------------------

Total for 1 adult passenger: $665.30
(as of Friday, February 22, 2008 7:50pm)

Fuel surcharge is not a tax. It's amazing that the US and EU governments still allow this type of false listing of airfares.

The airlines can give away air tickets for free and only charge for YQ surcharges of whatever they want.

I still don't understand? I get the fuel charge and taxes thing however, if you're going to the same place.. on the same day.. at almost the same time... why would the "extras" be different? taxes and fees should be the same for all flights? I guess it's just another scam.

Government- and airport-imposed taxes and fees vary with class of service and intermediate stopping points as well.

I agree that fuel surcharges are as much a part of the price of a flight as anything else, and not including them up front in price quotes is just another example of flimflam marketing, like $5.95 "shipping and handling" on something that cost 30 cents to manufacture and 50 cents to mail.