Iranian state television said another round of talks had been agreed for Istanbul in January.
EU foreign affairs chief Baroness Ashton described the talks as "detailed and substantive".
However, no major breakthrough appears to have been achieved and Iran's president has again called for the lifting of UN sanctions.
Mahmoud Ahmadinejad was quoted on Iranian state TV as saying: "If you come to the negotiations by cancelling all the nasty things and wrong decisions that you have adopted... lift resolutions, sanctions and some restrictions that you have created... then the talks will definitely be fruitful."
An Iranian official quoted by Agence France-Presse news agency said: "The negotiations will resume in end-January in Istanbul to discuss co-operation and find common points."
The talks in Geneva involved Iran's top nuclear negotiator, Saeed Jalili, along with Baroness Ashton and senior officials from the five permanent members of the UN Security Council - the US, Russia, China, France and Britain - plus Germany.
Iran Nuclear Talks In Geneva
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