Considering the Euro Media Hurth in Cologne?
A VT member wrote the following comment about visiting Cologne:
Tipping by keeweechic
While service charges are included in your restaurant bill, it's usual to round up the bill anywhere from the nearest dollar to 5%.
This should be given to the waiter/waitress when paying. Don't leave any money on the table. In a taxi, there?s no need to go beyond rounding up to the nearest dollar to tip unless the service is extraordinary.