The first rule of newsletter localization is to let localization professionals take care of the job, or at least someone who knows well the culture of the country/countries and language you are localizing the newsletter into.
We could write books explaining why, but we will probably not have your attention for that long. That is the nature of online marketing. Instead we will illustrate with a short, sweet and highly relevant example.

Not everyone celebrates Christmas

The holiday seasons is by far the most popular time to send newsletters. However, what many companies fail to understand is that not all people celebrate the same holidays. Some might even get offended if they are wished well for a wrong (in their eyes) holiday. So this must definitely be taken into consideration in the art of newsletter localization.

This is just a guess, but it seems doubtful that it will do your company any good to publish a newsletter localized into languages spoken in places where they do not celebrate the holiday used as an excuse to sell your products or services.
Also, you should consider that some people are more passionate about some holidays than others. For instance, the Greeks are much more passionate about Easter than Christmas, whereas the Scandinavians are much more passionate about Christmas than Easter.

Newsletter localization in 60+ languages

To see a complete list of the different holidays in each country you can click here, but the easiest and best solution would probably be to allow localization professionals take care your newsletter localization. And guess what? You’ve come to the right place for that.
At All-In Translations, we offer newsletter localization in 60+ languages. All our localization professionals are highly proficient native speakers of the target languages, meaning they know the culture of those languages and the countries, and they would never make a cultural mistake that would put the reputation of your brand at stake.