What does codeshare mean and how does it affect the way I redeem my miles?

Sometimes it’s also because SQ doesn’t operate a certain route so code sharing allows SQ to market those routes.

When you’re redeeming miles, do take note if you have no choice but have to take a certain airline (due to SQ not flying there) or just availability issues.

If your miles are not all in SQ yet, I would suggest you look at the different redemption rates of the airlines you’re interested in and the availability of the award tickets. Then transfer your miles to the ideal airlines. SQ award tickets can be quite hard to be redeemed.

Codeshare means 2 airlines sell the seats on a SINGLE plane operated by 1 of them.

For example, ANA operates a flight from SIN to Tokyo. But ANA tell SQ, want to codeshare? SQ says yes and that flight is available for sale on both SQ and ANA website. SQ will tell you it is codeshare with ANA when you are booking your flight and the flight is operated by ANA's crew onboard an ANA plane.

Does it affect the way you redeem your miles? Yes and No.
For No, you redeem using SQ website so it will be based off SQ's award chart so the flight from SIN to Tokyo sets you back 47,000 Krisflyer miles on business class, one-way.

For yes, the hard product (service, seat, food etc) is different. SQ business class seat is different from ANA business class seat. Just google the SQ regional business class seat and then google ANA regional business class seat and you can tell the difference.

In short, if you redeem a flight that is codeshare and operated by another airline, you might get a seat and services that are inferior to SQ.

Hope this helps and PM me if you need a more detailed explanation!