Here are the dates I’ve gather so far. Please let me know in comments of any others!
Outlander Season 3 will premiere in the USA on September 10, 2017.
In CANADA Outlander Season 3 will premiere on the W Channel on September 10.
The AUSTRALIAN premiere will be on Foxtel (Showcase Channel) EXPRESS on September 11.
Premiere date for Season 3 in NZ (on LightBox) is September 11.
The UK premiere date for Season 3 is September 11 – shown on Amazon Prime.
Premiere date for S3 in FINLAND is September 27.
Premiere date for S3 in ISRAEL is September 12.
Premiere date in DENMARK (on Viaplay) is September 11
Premiere date in the NETHERLANDS is February 18, 2018 on Netflix
Premiere date in NORWAY (on Viaplay) is September 11 @ 9pm.
Premiere date in GERMANY (on RTL Passion) is September 11 @ 7.30pm (19.30).
Premiere date for PORTUGAL (on TVSeries) is September 17
Premiere date for ITALY (on FoxLife) is September 29.