Archaeological materials are a finite resource, and efforts should be made to minimize destructive analyses. This can be achieved by using protocols combining extraction of several lines of evidence, which decreases the material needed for analyses while maximizing the information yield. Archaeological dental calculus is a source of several different types of biomolecules, as well as microfossils, and can tell us about the human host, microbiome, diet, and even occupational activities. Here, we present a unified protocol allowing for simultaneous extraction of DNA and proteins from archaeological dental calculus. We evaluate the protocol on dental calculus from a range of ages and estimated preservation states, and compare it against standard DNA-only and protein-only protocols. We find that most aspects of downstream analyses are unaffected by the unified protocol, although minor shifts in the recovered proteome can be detected. Protein recovery depends on both the amount of starting material and choice of extraction protocol, whereas DNA recovery is significantly lowered through the unified protocol. However, DNA recovery from dental calculus is generally very high, and we found no differences in DNA fragment characteristics or taxonomic profile. In conclusion, the unified protocol allows for simultaneous extraction of two complementary lines of evidence from archaeological dental calculus without compromising downstream analyses, thereby minimizing the need for destructive analysis of this finite resource.