The role of working memory (WM) in sentence comprehension has received considerable interest, but little work has investigated how sentence production relies on memory mechanisms. Three experiments investigated speakers’ tendency to produce syntactic structures that allow for early production of material that is accessible in memory. In Experiment 1, speakers produced accessible information early less often when under a verbal WM load than when under no load. Experiment 2 found the same pattern for given-new ordering (i.e., when accessibility was manipulated by making information given). Experiment 3 addressed the possibility that these effects do not reflect WM mechanisms but rather increased task difficulty by relying on the distinction between verbal and spatial WM: Speakers’ tendency to produce sentences respecting given-new ordering was reduced more by a verbal than by a spatial WM load. These patterns show that accessibility effects do in fact reflect accessibility in verbal WM and that representations in sentence production are vulnerable to interference from other information in memory.