When Does New Tax Year Start 2025. Calculate your tax for the new tax year at uktaxcalculators.co.uk. What changes will affect my small business in the 2024/25 tax year?.

Specifically, sections 3.05, 3.08, and 3.15(b) focus on. The 2024/25 tax year will then run from 6th april 2024 to 5th april 2025.