Connecticut Tax Residency (183-day rule)

Key parameters
Threshold	183 days
Period / Window	Tax year (1 Jan – 31 Dec)
Counting	Any part of a day
Alternative	Domicile
Additional requirements	Permanent place of abode

This applies to anyone with a dwelling available to them in Connecticut, whichever state they treat as their own. You are a Connecticut resident if either of these applies:

• Domicile — Connecticut is the place you intend as your permanent home and to which you return whenever you are away.
• Permanent place of abode plus days — you are domiciled elsewhere but maintain a permanent place of abode in Connecticut and are in the state for an aggregate of more than 183 days of the tax year.

The day rule reaches only people domiciled outside Connecticut — for anyone domiciled there, residence follows from domicile alone.

A permanent place of abode is a dwelling permanently maintained by you, whether or not you own or lease it. What falls outside the definition is a place kept only for a temporary stay to accomplish a particular purpose, along with quarters that are not really dwellings at all, such as barracks or a motel room.

The rule also runs in reverse. Someone domiciled in Connecticut who maintains no permanent place of abode in the state, keeps one elsewhere, and spends no more than 30 days there is treated as a nonresident for the year.

• The day rule does not touch people domiciled there. Someone domiciled in Connecticut is a resident on that basis alone, so counting days is beside the point until they change domicile.
• A motel room or barracks is not an abode. Quarters that are not genuine dwellings fall outside the definition however long you occupy them.
• A place kept for a defined purpose is not permanent. Accommodation taken for a temporary stay to accomplish a particular purpose does not satisfy the abode limb.
• You do not need to own it. A dwelling permanently maintained by you counts whether you own it, lease it, or it is held by your spouse.
• Two states can tax the same year as a resident year. Meeting the Connecticut test leaves your domicile elsewhere intact, so both states can charge you as a resident.

A resident is taxed on income from all sources while a nonresident pays only on Connecticut-source income, so an error usually surfaces as out-of-state earnings never reported while another state taxed the same income. The Department charges interest from the original due date and adds penalties for filing late and for underpaying, with greater exposure where an understatement is treated as deliberate. Professional tax advice is strongly recommended in situations like this.

A rented house and a full working year

You are domiciled in New York, rent a house in Greenwich for the whole year, and are in Connecticut most days. The abode is permanently maintained and the count passes 183 days, so you are a Connecticut resident.

Long stays in a motel

You spend around 210 days in Connecticut on a construction project, living in a motel throughout. A motel room is not a permanent place of abode, so the day rule does not attach despite the count.

Someone domiciled there who leaves cleanly

You are domiciled in Connecticut, sell your home, take a permanent home in Florida, and return for roughly 20 days. With no abode in the state, a home maintained elsewhere, and fewer than 30 days, you are treated as a nonresident.

• Connecticut Department of Revenue Services — Resident, nonresident or part-year resident
• Regulations of Connecticut State Agencies — Section 12-701(a)(1)-1, resident of this state