UPDATE | A new Avianca 'buy miles' promotion is paying out up to 125% more LifeMiles until September 30, which can be redeemed for travel on Thai Airways, Air Canada and across the Star Alliance.

For this promotion only, the usual 150,000 miles-per-year cap is boosted to 337,500 miles (including any bonuses earned), with miles sold in increments of 1,000 miles.

The number of bonus miles you'll pick up depends on how many you buy: purchases between 2,000 and 50,000 miles net double miles; buys between 51,000 and 100,000 net a 115% bonus, while buying 101,000 to 150,000 miles returns the full 125% boost.

All up, you could max out the offer by buying 150,000 miles with a 187,500-mile bonus for an all-out total of 337,500 miles – yours for US$4,950 (A$6,625).

That's almost enough for three return trips from Sydney to Bangkok in first class with Thai Airways when booking your travel outright, but can unlock significantly more opportunities through Avianca's 'flexible payment' option – more on that later.

But as flagged in our previous article, this special offer is only open to accounts that were created before the promotion began – so if you followed our advice and created a free LifeMiles account, now is the time to buy!

Remember: although you'll need to buy your miles before September 30, they can of course be redeemed for flights after this date.

The article below, written ahead of this promotion, explains more about the process of buying and using Avianca LifeMiles to book flights with Singapore Airlines, Thai Airways and other Star Alliance airlines.

PREVIOUS | Over the past year Australian Business Traveller has shared strategies for bulk-buying frequent flyer miles with United, American Airlines and Virgin America as a canny way to score business and first class seats at vastly discounted rates.

But this tactic isn't limited to US airlines. One of the most prized tricks of the travelling cognoscenti involves the little-known LifeMiles frequent flyer scheme of Colombian airline Avianca.

Avianca doesn't fly to Australia, yet that doesn't stop you from buying miles through LifeMiles – and because Avianca is a member of the Star Alliance family you can use those miles to book flights on other Star Alliance airlines such as Thai Airways, United, Air Canada and Lufthansa at far below the normal ticket cost.

For example, you could fly from Australia to London in business class for around $3,700 return with Star Alliance members Air China and Air India.

Another appealing option: jet to Vancouver and back with Air Canada in business class for around $3,300, or to Bangkok and back for an unbelievable $2,600 in first class.

As always, buying miles may let you travel at the pointy end without the premium price tag but it's not as straightforward as 'buy your miles, then book your ticket'.

Avianca LifeMiles has a few wrinkles of its own when it comes to booking those redemption flights, and you should always check the availability of award flights on your preferred travel routes and dates before buying miles.

Let's repeat that: always make sure there's a way to redeem miles to a destination and at a time that suits you... (did we say 'always'?)

Only when you've found something suitable should you pull the trigger and buy those miles, before then immediately redeeming them for your desired travel.

LifeMiles is one tricky beast, and the scheme is not for everyone, but it can be tamed. Here's how.

How to buy Avianca LifeMiles

Outside of any promotion periods, miles in the LifeMiles scheme can be purchased for US$0.033 each in multiples of 1,000 – or US$33 per block.

However, Avianca often runs two-for-one promotions on mileage purchases, reducing the cost per mile to just 1.65 US cents... but there's a catch: these deals are normally available only to existing members of the LifeMiles program.

The program is completely free to join and has no ongoing membership charges, so join online today – it takes just a few moments and means you should be in the running for Avianca's next promotion.

Each calendar year, LifeMiles members can buy up to 150,000 miles, which includes any extra miles earned during two-for-one promotions.

That's enough for at least two return business class trips to Europe London using a 'flexible payment' option – more on that later.

What you need to know

One reason that Avianca is a fave among frequent flyers: fuel surcharges, which typically cost hundreds of dollars on international flights, are absent from all LifeMiles award tickets.

Whether you book a flight with Avianca or one of its Star Alliance partners, you won't pay a cent towards the airline-induced 'fuel tax'.

All LifeMiles flight redemption bookings attract a US$25 'redemption fee', so if your circumstances allow you to book a return trip rather than two one-way fares, you'll avoid paying that fee twice.

Also, if your journey requires a connection – such as from Sydney to London via Bangkok – the maximum time you can spend in transit is eight hours: any more time in between flights and you'll have to book separate tickets.

That means you'd need to make one booking for Sydney to Bangkok and then another booking from Bangkok to London, forking out more miles than if you were to fly straight through, and also with two sets of 'redemption fees' to pay.

If you do manage to book connecting flights on a single ticket within that eight-hour window, it can also become a double-edged sword if an airline retimes your flights to have a gap longer than eight hours in between.

Not only would you be inconvenienced by losing the timings of your original flights, Avianca then won't re-issue your ticket until any new transits comply with the rule – so you'd need to choose new flights with a connection time of under eight hours, or cancel the ticket completely.

As situations like this are out of your control, we'd strongly suggest using Avianca miles for non-stop flights, but where a transit is required, choose an airline and hub with more than just a daily flight on the route.

Finally, you won't be able to book an award journey unless all flights on that journey are in the same cabin class (economy, business or first) – award availability must exist in the same cabin on even the shortest of connecting flights, so you might find better results by adjusting your destination city to one nearby (particularly within Asia and Europe).

Redeeming LifeMiles for Star Alliance flights

The rules are definitely restrictive and can work against you – but now that you're up to speed, it's time to uncover a few LifeMiles gems.

Sydney-Bangkok

A return business class trip on Thai Airways from Sydney to Bangkok will set you back 80,000 miles plus a small amount to cover Thai's additional taxes and charges.

That might sound like a good deal, but it's a solid chunk of that 150,000 pre-bonus cap.

You can get around the rule and book more of these great tickets by using the ‘flexible payment’ option at the bottom of the page – reducing the points cost to 32,000 with a co-payment of US$755 + taxes.

We'll assume you've played your hand well and held out to make your purchase during a double miles promotion – those 38,000 miles would cost US$627 at 1.65c/mile, so when combined with the $755 co-pay and $25 booking fee, you're looking at US$1,407 plus tax (A$1,880 on today's rate).

If you're booking those same flights the 'normal' way, you'd pay A$3,900, including the fuel surcharge but excluding other taxes and surcharges which are also added to Avianca redemptions, as mentioned above.

All your sleuthing and patience has paid off – that's over 50% cheaper than the retail fare!

Thai Airways also allows Avianca members to book award seats in first class – including to and from Sydney – which can be had for a straight 120,000 miles or 48,000 miles + US$1,133 (both plus taxes):

All up, the asking price is around A$2,605 before tax (48k miles @ 1.65c/mile + $1,133 + $25 booking fee = US$1,950)... tempted to book the normal fare? You might want to have a re-think – it's going for a whopping A$5,611 on those flights, making the mileage route less than half the cost of retail!

Again, we've included the fuel surcharges in the fare calculations, but have excluded the other taxes and surcharges – given that fuel surcharges aren't payable on Avianca redemptions, it's the most accurate way to compare the two.

Award availability between Sydney and Bangkok is reasonable – we were able to find seats on most flights later in the year, while also spotting seats on flights closer to departure (as above).

It's also worth highlighting that while Singapore Airlines used to be a great option for LifeMiles bookings to Asia, award tickets on SQ's Australian flights are now incredibly difficult to locate: to the point that we were unable to find a single award seat on any dates we searched.

Sydney-Vancouver

Another way to use your LifeMiles is on Air Canada's Sydney-Vancouver flights, but note that business class award seats on this route are quickly snapped up, so again, be sure to check your dates.

If the stars align, you'll be looking at either 160,000 LifeMiles outright or as few as 64,000 miles plus a co-payment of US$1,511, along with any government taxes payable:

The latter is also the best option for travellers who aren't also collecting miles in Avianca via other means, as the most you can buy in a single year is capped at 150,000 miles – 10,000 miles less than the outright cost of this ticket.

All up, you'd fork out A$3,337 (US$2,526) plus government taxes for business class flights that Air Canada would otherwise sell for around A$9,092 plus government taxes and fees.

That's less than half the cost of buying a ticket the 'normal' way – 63.2% cheaper to be precise – and gets you the same seat on the same flight to the same destination.

Award seats on other flights to North America such as with United to Los Angeles and San Francisco can also be a good option, but availability is often quite limited.

Sydney-Europe

If London’s call beckons, you'll need either 170,000 miles outright or 68,000 + US$1,605 in business class for a return trip, plus taxes.

Again, and certainly not helped by the 'eight hour transit' rule, it can be tricky to find seats on the dates you need to travel – but if you're flexible with which cities you fly through, there's a good chance you can make something fit.

For example, if your ideal route is from Sydney to London, consider flying internationally from Melbourne or Brisbane instead, or using other European airports such as Zurich, Frankfurt, Munich, Paris, Rome and Milan.

Using dates in April 2016, we were able to stitch together a Sydney-Paris trip with the outbound journey with Air China via Shanghai, and the return with Air India via Delhi:

All up, it'd cost US$1,122 to buy the 68,000 miles you'd need during an Avianca 2-for-1 promo, and with a co-payment of US$1,605 and the redemption fee of US$25, that's just A$3,675 return in business class, plus any government taxes and fees.

Before you book...

Once you've booked your preferred flights via LifeMiles, any changes and cancellations can only be made over the phone – attracting fees of US$50-150.

Furthermore, any cash amounts paid in lieu of miles through the 'flexible payment' stage won't be refunded if your booking is cancelled – instead, your mileage balance will receive a boost equivalent to the full mileage asking price for that journey.

For example, if you shelled out 68,000 miles and US$1,605 for a return trip to London, a cancellation would see a credit of 170,000 miles, rather than a refund in the manner originally paid.

We also wouldn't recommend sitting on your miles for too long, as Avianca changes the redemption rates from time to time and sometimes without warning, such as in 2013 when the cost of some first class journeys increased by 50,000 miles overnight.

Avianca award costs and exchange rates used in this section of the article correct as of July 10 2015.

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