Summer is coming soon in the northern hemisphere, which means it’s time for the annual business class fare sales. As business travel slows, paid premium traffic slows along with it. So bring on the sales!

Many of these sales aren’t advertised as such. The airlines simply load a lower business class fare into the system, and it’s not necessarily available every day on every flight. These are usually “Z-fares,” i.e., they have a fare code that begins with the letter Z. These come with more restrictions than a typical business class ticket, and will often need to be purchased relatively far in advance — sometimes as far as 60 days.

Bottom line: Before you hit “purchase” on an expensive international coach ticket, check the business class fare.

Beyond the big carriers and their summer discounts, there are a couple other business class offers worth mentioning:

All-business class Silverjet is rolling out its own loyalty program — the “Freequent Flyer Program”, har har. If you join the club and buy a ticket on the airline, you get a redemption code for a free ticket. The promotion ends May 25, 2007.

Oasis International Airlines, the low-cost long-haul London to Hong Kong carrier (that plans to fly to Hong Kong to Oakland later this year) is similarly featuring a buy-one-get-one-free offer on their Hong Kong-London route. Buy one business class ticket for , get a transferable voucher for another business class ticket free. £1595 (~US$3200) including taxes buys you both tickets. Purchase the first ticket by June 15, 2007. The voucher is good through March 2008. (via RoadGladiator)

Related:
- Why are there no Y-UP fares to Europe or Asia?

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