Privacy-enhancing attribute-based credential (Privacy-ABC) technologies use different cryptographic methods to enhance the privacy of the users. This results in important practical differences between Privacy-ABC technologies, especially with regard to efficiency, which have not been studied in depth, but is necessary for assessing their suitability for deployment on devices with limited computational power and for highly dynamic scenarios. In this paper, we compare the computational efficiency of two prominent Privacy-ABC technologies, IBM’s Idemix and Microsoft’s U-Prove, covering all known Privacy-ABC features. The results show that presentation overall in general is more efficient with Idemix, whereas U-Prove is more efficient for the User side (proving) operations during the presentation, and overall when there are more attributes in a credential. For both technologies, we confirmed that inspectability, non-revocation proofs, and inequality predicates are costly operations. Interestingly, the study showed that equality predicates, the number of attributes in a credential, and attribute disclosure have a very small influence on the efficiency for both technologies. Finally, we discuss important trust considerations specific to Privacy-ABCs.