I read somewhere that 99 days out is statistically the best time to buy International Flights. We buy international tickets several times per year (mostly NOT for cruises). I generally start looking about 6 months out to get an idea of the flight times I want, prices, etc. I suggest keeping an eye on how many seats have sold on the flight you want... if it's quite full - don't hesitate to buy when it looks like a good price. If it's pretty empty - WAIT! We had to buy 4 tickets to Amsterdam for a cruise next week... and prices were going up in $50 increments every few days (this was 4-5 months out) and I got nervous that I had waited too long. But the flight was only 20% full, and prices started to drop back after a few nervous weeks. (Prices direct with airline were hovering between $1550-$1750pp.) I checked with Choice Air right at 100 days out and bought tickets on my desired airline/days/times for $1325. (When airline was still at $1570.) So x4 that was quite a good savings! I will say it was "deeply discounted fare"... so I won't get the full amount of frequent flier miles and probably won't get upgraded to "delta comfort+" even with my husband's status. But saving $1000 seemed worth it. Choice Air does check the codeshare savings... we knew exactly the fights we wanted (on Delta), and we got those flights, but the outbound was booked via Delta, and the return via KLM (though still a Delta operated flight.) Good luck!