The Federal Fiscal Court rejected maintenance payments to the mother living in Hungary because the cash payments were not sufficiently proven. In the case of maintenance payments to recipients living abroad, the parties involved are particularly obliged to cooperate in clarifying the matter and to obtain evidence. The evidence required to prove a fact depends on the circumstances of the individual case (BFH ruling of 09.03.2017, VI R 33/16).
However, the BFH grants a relief: "The fulfilment of the obligations to clarify the facts and to provide for and obtain evidence must be necessary, possible, reasonable, and proportionate." For example, in the case of a civil war, evidential relief regarding the procurement of official certificates may be considered.
For cash payments to relatives abroad, the tax office requires increased proof: The tax office requires you to provide domestic evidence of the availability of the corresponding funds, e.g. withdrawal receipts. There must be a connection between the withdrawal and the respective cash payment, which must not exceed two weeks. If you claim cash payments made during visits, you must also prove the trip, for example with tickets, fuel receipts, border crossing stamps, flight tickets, visas, etc. You must prove cash payments with a recipient confirmation. This must include: Name and address of the maintenance payer and recipient, date of payment, place and date of issue of the confirmation, recipient's signature.