Introduction: Living with dementia is challenging for persons with dementia (PWDs) and their families. Although multi-component intervention, underscored by the ethos of person-centred care, has been shown to maintain quality of life (QOL) in PWDs and caregivers, a lack of service integration can hinder effectiveness. Methods: CARITAS, an integrated care initiative provided through a hospital-community care partnership, endeavours to provide person-centred dementia care through ambulatory clinic consults, case management, patient and caregiver engagement, and support. We evaluated CARITAS’ clinical outcomes and cost-effectiveness with a naturalistic cross-sectional within-subject design. We assessed patients’ function, QOL, and behavioural problems post-intervention. We estimated CARITAS’ cost-effectiveness from a patient’s perspective, benchmarking it against other dementia treatments and Singapore’s Gross Domestic Product (GDP) per capita. Results: CARITAS care significantly improved health utility (p < 0.001), reduced caregiver burden (p < 0.001), and improved PWDs’ behavioural problems (p < 0.001) related to “memory” (p < 0.001), “disruption” (p = 0.017), and “depression” (p < 0.001). CARITAS’ benefits (d<sub>RMBPC</sub> = 0.357, d<sub>EQ5D index</sub> = 0.328, d<sub>ZBI</sub> = 0.361) were comparable to those of other pharmacological and non-pharmacological interventions for dementia. CARITAS costs SG$133,056.69 per quality-adjusted life years gain, yielding an incremental cost-effectiveness ratio of 1.31 and 1.49 against the cost of donepezil in patients with mild Alzheimer’s disease and Singapore’s GDP per capita in 2019, respectively, falling within the cost-effectiveness threshold of 1.0–3.0. Discussion: CARITAS integrated dementia care is a cost-effective intervention that showed promising outcomes for PWDs and their caregivers.