Objective: To evaluate the acceptability, test–retest reliability and validity of the Longer-term Unmet Needs after Stroke monitoring tool. Design: A questionnaire pack was posted to stroke survivors living at home three or six months after stroke. A second pack was sent two weeks after receipt of the completed first pack. Setting: Stroke survivors living at home across England. Subjects: Stroke survivors were recruited from 40 hospitals across England, in two phases. The first with an optimal cohort of patients, the second to capture a broader post-stroke population, including those with communication and/or cognitive difficulties. Patients were excluded if they required palliative care or if permanent discharge to a nursing or residential home was planned. Main measures: The questionnaire pack included the Longer-term Unmet Needs after Stroke tool, General Health Questionnaire-12, Frenchay Activities Index, and Short Form-12. Results: Interim analysis of phase 1 data ( n = 350) indicated that the tool was sufficiently robust to progress to phase 2 ( n = 500). Results are reported on the combined study population. Of 850 patients recruited, 199 (23%) had communication and/or cognitive difficulties. The median age was 73 years (range 28–98). Questionnaire pack return rate was 69%. For the new tool, there was 3.5% missing data and test–retest reliability was moderate to good (percentage item agreement 78–99%, kappa statistic 0.45–0.67). Identification of an unmet need was consistently associated with poorer outcomes on concurrent measures. Conclusions: The Longer-term Unmet Needs after Stroke tool is acceptable, reliable, can be self-completed, and used to identify longer-term unmet needs after stroke.