I recently heard a piece of trivia that Germany had not paid the debts incurred from its defeat in WWI until very recently in 2014. However, that raises an obvious problem: Germany was 2 different countries during the Cold War, and was then reunified a couple decades afterward. Did they split the bill, or was there a different solution?
Germany was divided into four occupied areas after World War II - three of these merged into the Bundesrepublik Deutschland (FDR) and the soviet zone became the Deutsche Demokratische Republik (GDR). Both nations cannot be considered to be fully independent. Until the German Reunification in 1990 and the 2+4-treaty (Vertrag über die abschließende Regelung in bezug auf Deutschland) which entered into force in March 1991 there was only a limited sovereignty for both FDR and GDR.
Therefore there was no peace treaty after World War II with Germany and the question of legal successorship of FDR or GDR was quite difficult and open to legal dispute.
Regarding the reparations from WW I there would have been no agreement between the two states as both did not recognise the other (the FDR esp. refused to accept the legitimacy of the dictatorial communist regime in east Germany).
The issue about the Versailles reparations was addressed in the London Agreement on German External Debts in 1953 between the FDR (West Germany) and states of the Western bloc. The FDR paid around 14 billion Deutsche Mark until 1983 (meaning more than 20 billion dollars today adjusted for inflation). A smaller part of the obligations (mostly interest) was only to be paid after a Reunification and that is what happened after 1990. Around 250 million DM were paid after that.
Obligations by Eastern Bloc countries were largely ignored by the FDR. The GDR paid reparations to eastern countries for a time (esp to SU) but soon there were Freundschaftsverträge (friendship and cooperation agreements) dictated (more or less) by the Soviet Union. In 1953 the SU suspended further reparations from the GDR (which at the time was on the verge of economic collapse anyway).
Up till today some countries have addressed that Germany owes them war reparations (though as far as I’m aware these are WWII reparations). Especially Greece and Poland have laid claims in recent years. But this is another interesting yet complex matter.