The research was admittedly released by Virgin Money ? a competitor to all those credit cards available to South Africans that do offer 'free air miles' ? yet it does bring into question just how rewarding loyalty programmes are.

Moreover, it serves as a warning to customers bowled over by credit card adverts punting those 'free' air miles.

The most expensive credit card

Virgin have based their calculations on the fact that each mile or point accumulated ? which you will later redeem to get a free flight ? requires you to spend a certain amount of money. This varies from R5 to R12.50 per mile.

South Africans on average are said to spend R3000 a month on our credit cards, as industry figures show, which is then multiplied by the number of points or miles required to get the free flight.

The result? Using the most expensive credit card, the Absa rewards miles offering, you have to pay R421 000 over a period of 11.5 years ? and spend an additional R1032 in credit card fees over the period ? to qualify for a single free domestic flight.

Of the other banks, Nedbank's Greenbacks miles programme with SAA Voyager means you'll pay R338 750 over 9.4 years ? with R2700 extra being paid in credit card fees ? for a free flight. For Standard Bank (with British Airways) it comes to R225 000 over 6.25 years (with R1435 in extra fees).

FNB's offer was the cheapest of the big four banks, equaling R99 980 over 2.8 years, and paying R885 in credit card charges, to get that free domestic flight.

Not an award

Of the other popular credit cards, SAA Voyager's Classic credit card (Visa) means you'll need to spend R225 000 over the next 6.25 years, paying R2100 in fees, to qualify for a free trip, while using their American Express card equals R127 000 over 3.3 years, with R1200 in card fees. When you apply for a SAA Voyager credit card, you receive both the Visa and Amex cards.

However, according to Manoj Papa, Head of SAA Voyager, Virgin's calculations have not taken into account extra benefits, including double miles on eligible spend for the first three months.

According to Papa's calculation, taking these benefits into consideration, if you use the SAA Voyager Classic credit card (American Express), you'll pay R81 900 over 2.28 years, paying R600 in credit card fees. Moreover, he says, you'll always use the Voyager Amex card before the Visa card, "as this card has the better mileage earning ratio of the two".

Papa says, "It should also be emphasised that for many card holders spend on the card is an accelerator to help them earn enough miles for a free flight and is not necessarily a means in itself to obtain an award."

Dream destination

SAA in particular has aggressively advertised its Voyager credit cards as bringing "your dream destination closer" ? allowing you to "get off the ground and on your way to your dream destination, faster than you could possibly imagine" by earning free air miles, its advertisement on Nedbank's website says.

Moreover, it's handy to remember that airport taxes are not included when redeeming your free flight ? which according to Papa is standard with frequent flyer programmes across the world.

Also, when you redeem your air miles, they are subject to seat-availability.

Says Virgin Money's Gavin Muller in a statement, "No matter what type of air miles' programme your existing credit card offers, the objective of each one is to egg you on to spend as much money as possible on your particular credit card."

"It's about time card holders are made aware that the free flight they think they are getting will land up costing them thousands of rands."

Addendum: Since publishing the article, Virgin has recalculated the figures following complaints by some of the banks. According to Virgin, instead of debating the figures, they have accepted them and changed the research table and press release numbers. They add that they're happy to do this because "it's still a pretty big rip-off".

Here are the updated figures (only those figures that have changed are shown):

On average, you have to spend R171 324 over nearly five years on your credit card in order to qualify for a ?free? return flight between Johannesburg and Cape Town.

Absa's reward miles offering is now R201 500 over 5.6 years, with fees amounting to R752.

Standard Bank equals R135 000 over 3.75 years, with fees of R1460.

FNB's programme comes to R99 800 over 2.8 years, with fees of R885.