Background: Evidence should guide decisions in aphasia practice across the continuum of stroke care; however, evidence-practice gaps persist. This is particularly pertinent in the acute setting where 30% of people with stroke will have aphasia, and speech pathologists experience many challenges implementing evidence-based practice. This has important consequences for people with aphasia and their close others, as well as speech pathologists working in acute settings. Aims: This study protocol details how we will target practice change using a behavioural approach, with the aim of promoting the uptake of synthesized evidence in aphasia management post-stroke in the acute hospital setting. Methods & Procedures: We will conduct a mixed-methods before-and-after study following the Knowledge-to-Action (KTA) framework. Researchers, speech pathologists and people with lived experience of aphasia will collaborate to identify and prioritize practice gaps, and develop and implement changes to clinical practice based on the Theoretical Domains Framework and Behaviour Change Wheel. Discussion: This study may provide a template for acute stroke services in how to use an implementation science approach to promote the application of synthesized evidence into routine clinical practice to ensure people with aphasia receive high-quality services. Collaboration among researchers, healthcare providers, people with aphasia and their close others ensures that the identification and targeting of practice gaps are driven by theory, lived experience and the local context.