This paper seeks to find whether the spectrum auctions in Sweden have been conducted efficiently and if there is a de facto model that suits all auctions. The efficiency is conditions that emphasise truthful bidding, price discovery and limits collusive behaviour. The paper compares three different auction models used in Sweden, a beauty contest used in the allocation of 3G spectrums, and the auction model selected for the upcoming 5G spectrum auction. The auction models are as follows: first and second-price sealed-bid auction, SMRA and CCA. We found that beauty contests should not be used in any spectrum allocation as it did not meet the criteria of efficiency outlined in this paper. The first-price sealed-bid auction is not a suitable format for spectrum auctions. According to the theory, it generates equivalent revenues on average as the second-price format, which shows a higher degree of efficient allocation. We found that depending on the blocks sold, both SMRA and CCA can result in somewhat efficient results, but they are not suitable for a single object auction. We found that no de facto auction format is suitable for every spectrum auction to be conducted in the future, but instead that the auction format is dependent on the characteristics of the individual auctions.