Aussie motorists now have three way to earn airline frequent flyer points when they fill up their tank.

Flash your Woolworths Rewards card to earn Qantas Points at Caltex-Woolworths service stations; your Virgin Australia membership card at BP outlets to pocket a serve of Velocity Frequent Flyer points; or wave a Flybuys card at Coles Express (Shell) servos for Etihad Guest miles.

But which is the best option when it comes to earning points at the pump? Follow along as we fill up a standard 50 litre petrol tank at each outlet.

Woolworths Rewards at Caltex: earning Qantas Points

From August 31, Woolworths Rewards members will earn one Woolworths Point per dollar spent on fuel at some 530 Woolworths Caltex outlets (although you don't get points for in-store buys at Star Mart and Star Shop).

Once you've collected 2,000 Woolworths Points they can be converted into 870 Qantas frequent flyer points.

That's a net earn rate of 0.43 Qantas Points per dollar spent (one point for every ~$2.30 spent).

What’s more, if you’ve earned a 4c/litre fuel savings voucher by spending $30 or more at a Woolworths supermarket beforehand, you can enjoy your discount while also earning points on the final amount paid.

For example, buy 50 litres of fuel at 119.9c/l and the pump will read $59.95.

Using one of those discount vouchers brings the cash cost down to $57.95, on which you’d earn 57 Woolworths Points – equal to 24 Qantas frequent flyer points.

Total reward on a 50 litre tank, with voucher: $2 saving + 24 Qantas Points

BP: earning Virgin Australia Velocity points

Earning Velocity Frequent Flyer points at BP is as simple as swiping your Velocity card through the terminal before you pay – but unlike Coles and Woolworths, you’ll earn two Velocity points per litre of fuel purchased.

To compare like-for-like across programs, when BP is also selling petrol for 119.9c/litre you’d earn the equivalent of 1.668 Velocity points per dollar spent, or 100 Velocity points on that same 50 litre tank, costing you $59.95 overall.

As an added bonus you can also earn two Velocity points per dollar spent in-store with BP – such as on drinks, snacks and newspapers – but to keep our comparison strictly to fuel only, we’re not factoring this in.

Total reward on a 50 litre tank: 100 Virgin Australia Velocity points

Flybuys at Coles Express: earning Etihad Guest miles

Fill up at Coles Express and scan your Flybuys card to pocket one Flybuys point for every $2 spent (0.5 points per dollar).

You can then convert 10,000 Flybuys points into 4,000 Etihad Guest miles, which sees you earning the equivalent of just 0.2 Etihad Guest miles per dollar spent (one mile per $5 spent) – but like Woolworths, you can earn points while also redeeming a 4c/l fuel savings voucher.

Read: Your unofficial guide to the Etihad Guest program

Buy that same 50l tank at 119.9c/l with a fuel discount voucher and the sticker price also falls from $59.95 to $57.95, on which you’d earn 28 Flybuys points, equal to 11 Etihad Guest miles.

Total reward on 50 litre tank, with voucher: $2 saving + 11 Etihad Guest miles

Earning points on petrol: how they compare

Coles Flybuys is your worst choice with a very low earn rate (less than half the number of points compared to Woolworths Rewards/Caltex), and you have to pocket a whopping 10,000 Flybuys points before they can be converted into frequent flyer points.

Woolworths Rewards pairs more points with an achievable conversion rate of 2,000 Woolworths Points to 870 Qantas Points, and when combined with a 4c/l fuel discount voucher is the better option if you'll be spending your frequent flyer points only on economy flights.

BP+Velocity pumps out 76 frequent flyer points more than Woolies in lieu of a $2 fuel saving on that 50l tank, but which can be used to unlock between $3.80 and $5.30 in value when booking business class award flights: proving the most rewarding option overall.

Also read: Woolworths brings back Qantas Points from August 31

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