OBJECTIVES Upper limb spasticity (ULS) secondary to stroke has a considerable patient and caregiver burden, particularly with regards to pain, activities of daily living and mobility. Botulinum neurotoxin-A (BoNT-A) injections are effective in treating ULS. We aimed to calculate annual BoNT-A treatment cost of ULS on a per-patient basis, and the expected overall annual budget impact of BoNT-A treatment in Germany using static and dynamic market share scenarios. METHODS A budget impact model for BoNT-A use, adopting a German healthcare system perspective, was developed. Two market-share scenarios were modelled over 5 years. While the static scenario assumed current market shares (abobotulinumtoxinA, 36%; onabotulinumtoxinA, 26%; incobotulinumtoxinA, 38%) to remain constant over time, the dynamic scenario assumed market share of abobotulinumtoxinA to rise up to 76% across 5 years. Epidemiologic data inputs were sourced from the most recently published literature, unit costs for BoNT-As from the Lauertaxe (pharmacy purchase price [PPP] level), and market share assumptions from IMS Health (Market Sizing). Equivalence of the 3 BoNTAs in terms of efficacy and safety is assumed and therefore no differential use of medical services or other goods. RESULTS Annual BoNT-A drug costs per ULS patient were 3 463€, 5 603€, and 5 410€, respectively, with prescribing patterns following SmPC recommendations for abobotulinumtoxinA, onabotulinumtoxinA, and incobotulinumtoxinA. The total drug costs were decreased by between 1 231 861€ (-4%) in year 2 and 5 133 684€ (-17%) in year 5 by shifting the market share to abobotulinumtoxinA. Sensitivity analyses showed that the number of patients treated with BoNT-As, time to re-injection, and dose per injection were the most influential parameters on budget impact, impacting both drug acquisition costs and physician visits. CONCLUSIONS Increased use of abobotulinumtoxinA compared with incobotulinumtoxinA and onabotulinumtoxinA for ULS in Germany could potentially reduce the total cost of treatment.