Tax situation when marrying a foreigner

Such things get a bit complex and have more to do with German tax rules than with immigration. Obviously it is to your advantage to officially register your marriage as soon as possible once back in Germany.

From what I've read, I agree with what Beppi wrote that he would have to be in Germany under the German tax system first before you can opt to file a joint tax return. Luckily, one doesn't need to have had this for the whole year. Thus if you manage to get him to Germany, with your marriage registered, before the end of the year, you can file jointly for the whole year.

In any case, foreigner or not, living wherever, a couple cannot live separately all of the time and file a joint return. 

I found a bit of information (in German) about the subject at the following sites although they are not so detailed concerning  exactly your specific situation.

https://www.steuertipps.de/steuererklae … r-so-gehtshttps://www.buhl.de/steuernsparen/einze … besonders/