Connecticut Income Tax 2025 Instructions. The state's new earned income tax credit change, which took effect retroactively for 2023 and will become available when recipients file their personal. Deadline for taxpayers who got an ct tax extension to file their connecticut income.

For tax years beginning on or after january 1, 2025, the connecticut income tax rate on the first $10,000 and $20,000 of connecticut income earned by single filers. File your 2023 connecticut income tax return online!