For the frequent flyer for whom the cheapest price is not a consideration and who does not wish to take pot-luck at the airport on getting an upgrade, there is a “sure” way of accomplishing this.
If you fly regularly within your own country, choose a specific airline and join their frequent flyer program. Then, when you are ready to book your less frequent international trips, book way in advance and use your miles to upgrade.
Why way in advance? Because the airlines only allocate about 3 to 5 seats in business class for upgrades. Should you have to wait-list for business class on one of your sectors, the higher the tier or status of your membership, the better your chance of jumping the queue ahead of those on a lower tier membership, who may have wait-listed before you. This has been proven over and over again in the industry!
Obviously, by doing the above, it will restrict you to that specific airline’s prices. You may need to have a generous boss or an understanding financial controller for this to be of benefit as it will cost more than if you take the cheapest airline for each flight. Of course if it is your company then you will have little problem in implementing this!
It is noteworthy to mention here, that certain airlines allow companies to accrue mileage in their company name and thus the person that controls the travel budget will get to decide who uses the miles and for what, be it upgrades or ‘free’ (*) economy tickets. Even low cost carriers offer small to medium businesses corporate rates and more flexible fares on those rates. Flexibility in terms of changing and cancellation fees.
(*) As usual with the use of the word free, it is not entirely free because the taxes must still be paid even on tickets bought with air miles. You cannot pay taxes with airmiles. There may even be a small additional fee to pay when doing an upgrade to business class: certain ticket taxes are higher for business class than for economy tickets. In addition, some airlines charge what they term “expediting fees” for issuing loyalty programme tickets.