If you’re regularly bound for Bangkok or beyond on Thai Airways, it’s worth getting to know the airline’s Royal Orchid Plus frequent flyer scheme. As a Star Alliance airline, Thai’s Royal Orchid Plus members can also grab points when jetting off with the likes of Singapore Airlines, Air New Zealand, United Airlines, Air Canada and Air China.

The beauty of alliances is that you can pick and choose which loyalty program you belong to – you aren’t trapped only to the program of your most-travelled airline.

For example, Singapore Airlines’ KrisFlyer scheme also lets you earn and burn on Thai Airways, as does Aegean’s Miles&Bonus – which could also net you Star Alliance Gold status in a single flight.

Nonetheless, whether you’re often flying to or through Bangkok or only fly with Thai on your annual holiday, here’s what you need to know about Royal Orchid Plus.

Along with Thai Airways flights, Royal Orchid Plus lets travelers earn and redeem points on all Star Alliance member airlines.

From Australia, that includes Singapore Airlines, United Airlines, Air Canada, EVA Air, Asiana Airlines, Air New Zealand, South African Airways, Air China and Star’s newest member, Air India.

Further afield, Royal Orchid Plus extends its grasp to ANA, Lufthansa, Swiss Airlines and Turkish Airlines, among others.

It’s free to join, so zip across to the Thai Airways website to enroll. And, by joining online, you’ll pocket a bonus 2,500 miles with your first Thai Airways flight.

You’ll also be able to set your seat and meal preferences when signing up, so by attaching your Royal Orchid Plus (ROP) membership number to future Thai Airways bookings, these requests will automatically be carried over.

Don’t forget to also quote your ROP number when travelling with Thai’s many partners, as there are miles to be earned there too – you’ll just need to set your travel preferences manually.

Speaking of points, your miles expire exactly three years from the end of the quarter in which they were earned if they haven’t yet been redeemed.

For example, if you earned 4,000 miles on September 15 2014 and 3,500 miles on October 2, the first batch would expire on September 30 2017, while the second set faces extinction on December 31 2017.

That rule doesn’t apply to Platinum members, although accounts that go two years without earning or redeeming any miles will be closed and the balance wiped completely – even if the points weren’t due to expire for a further year.

Moving beyond the entry-level (purple) tier, your status will progress through Silver and Gold as you fly more with Thai and its partner airlines, while Platinum is exclusively the domain of Thai’s frequent-flying business and first class passengers.

How far you progress is based on your travel history over both the last 12 and 24 months, with the more favorable of the two used to calculate your membership tier.

That’s done by looking at your rolling balance of ‘qualifying miles’ every month (also referred to in the program as ‘Q miles’) – which you’ll earn when flying with any Star Alliance airline.

Q miles generally mirror the number of regular, redeemable miles you’ll earn on your travels, although much like Qantas status credits, Q miles can’t be swapped for award flights or business class upgrades.

You’ll earn the most Q miles in Royal First Class and Royal Silk Class (business), while all eligible economy fares earn one Q mile per actual mile flown.

On the cheaper G, V and W economy ‘fare buckets’, you’ll earn redeemable miles at between 25 and 50% of the actual distance flown. While you’ll also pile up Q miles on those tickets, they only help to reach or retain Silver status – for Gold, V, G and W tickets aren’t counted.

With Thai’s Star Alliance partners, you’ll earn both qualifying and redeemable miles based on ROP’s partner earning rates.

After piling up 10,000 Q miles over 12 months or 15,000 Q miles over 24 months, you’ll move up to Royal Orchid Plus Silver status – yours for two years from the qualifying date.

That’s easily done by making one return trip from Sydney, Melbourne or Brisbane to Bangkok and back in business class, or even a one-way trek to London from Australia’s east coast or Perth on most economy fares.

The benefits aren’t many, but you’ll get an extra 10kg of checked baggage on Thai Airways flights, along with priority baggage tags to get you on the road faster.

ROP Silver members also have Star Alliance Silver status, which also doesn’t bring many discernable perks – but if you’re waitlisting for a flight or travelling on standby, priority treatment could see you flying out ahead of another passenger.

Over 12 months, 50,000 Q miles or 40 international Thai Airways flights is enough to take out the Gold, while 80,000 Q miles over 24 months gets you there as well.

Excluded from Gold-level Q mile calculations are those cheaper G, V and W fares – so as a rule, if you’re earning one point per mile, you’re on track for Gold.

At the pointy end, flying Sydney-Bangkok-London and back in business class twice each year would see you more than qualify, reeling in roughly 26,517 Q miles on each visit to the UK.

Every time you reach or maintain Gold, you’ll get a bonus 5,000 miles and a free round-trip upgrade certificate.