If in trouble or in doubt with your tax declaration for Luxembourg use Taxx.lu.The company behind the online tool is called Taxx S.àr.l. and belongs to Athome group which is well known for its website Athome and Luxauto. The tool itself is very much self explaining as the only purpose it has is to support you with your luxembourgish tax declaration. This sounds somehow bit negative but it is not meaned that way as the tool itself is great. Its available in 4 languages, English, German, French, Luxembourgish and next to the website they also offer an app for Andriod and iOS. Doing you tax declaration with Taxx.lu is easy as they guide you step-by-step and give you hints and recommandations which kind of data you need to provide. However, if you want more assistance you can benefit from booking a premium package. Pricing obviously varies depending on the service level you choose, basic version starts with 50 €, which is rather cheap compared to a tax advisor and taking into consideration the possible payback from your tax office.