This study investigated the flexural behavior of ultra‐high‐performance concrete decks with an innovative joint of fiber continuity at the joint interface. An experimental program with 21 specimens was designed and tested. Four types of joints were studied, that is, lap‐spliced rebar, fiber continuity, combination of fiber continuity and lap‐spliced rebar, and combination of additional reinforcement and lap‐spliced rebar. Finite element models were built and benchmarked using the test results. The influence of reinforcement ratio and interfacial fiber content was investigated. Experimental and numerical results showed that a joint with a combination of fiber continuity and lap‐spliced rebar achieved similar flexural performance as cast‐in‐place decks. In addition, the design theory of the Swiss code (SIA 2052‐2016) was recommended with promising accuracy in estimating the flexural capacity of precast ultra‐high‐performance concrete decks, based on the tensile strength of joint interface with various fiber contents.