Connecticut — Tax Residency Rule

Summary

Day threshold

More than 183 days

Window

Taxable year (usually the calendar year)

Also requires

A permanent place of abode in CT

Effect

Worldwide income taxed

Basis

Conn. Gen. Stat. § 12-701(a)(1)(B)

Connecticut treats you as a statutory resident for income tax if both are true in the same taxable year: you spend more than 183 days in the state and you maintain a permanent place of abode there. To stay outside this rule, keep your Connecticut days at 183 or fewer, or avoid keeping a permanent abode in the state. A separate domicile test can make you a resident even below the threshold.

Who it applies to

This matters most if you are:

• A remote worker or frequent traveler spending long stretches in Connecticut each year.
• Someone who keeps an apartment or second home in Connecticut while living or working elsewhere.
• A person moving to or from Connecticut mid-year, where days and abode overlap for part of the year.
• Anyone whose true, fixed, permanent home (domicile) is arguably in Connecticut.

It applies to individuals based on presence and housing, not citizenship or visa status. The rule sits alongside — and is separate from — the federal US tax rules.

The rule — and why it exists

Conn. Gen. Stat. § 12-701(a)(1) defines "resident of this state" through two independent routes:

• Statutory residency (the day-count route). A person not domiciled in Connecticut who maintains a permanent place of abode in the state and is there for an aggregate of more than 183 days of the taxable year is a resident. Members of the US armed forces on active service are excluded.
• Domicile. If Connecticut is your true, fixed, permanent home, you are a resident regardless of day count — unless you meet the 30-day safe harbor or the 548-day foreign-presence exception.

The "permanent" part does real work. The DRS regulation gives its own example: someone domiciled in another state who is assigned to a Connecticut office for a fixed and limited period and uses an apartment there is not a resident even after more than 183 days, because the abode is not permanent. Make the same assignment indefinite and the apartment becomes a permanent place of abode — and more than 183 days makes that person a resident.

Counting the days

1. 1Count each day, or part of a day, you are present in Connecticut during the taxable year (for most people, 1 January to 31 December).
2. 2The count resets at the start of each new taxable year — it is a fresh annual tally, not a rolling window.
3. 3Any part of a day counts as a full day. The DRS regulation's only exception is a part day spent in the state solely in transit to a destination outside Connecticut.
4. 4Day 184 is the trigger: you become a statutory resident once you exceed 183 days while also maintaining a permanent place of abode in the state.

The regulation requires a non-domiciliary with a Connecticut abode to keep records available to prove they spent 183 days or fewer in the state — the burden is on you, not on the Department of Revenue Services.

Examples

Example 1 — clearly resident by days

You rent a year-round apartment in Stamford and are physically present in Connecticut for about 210 days in the year. You exceed 183 days and hold a permanent abode, so you are a statutory resident and Connecticut can tax your worldwide income for that year.

Example 2 — over 183 days but no abode

You spend 200 days in Connecticut but always stay in short-term hotels and keep no dwelling suited to year-round living. The abode condition is not met, so the statutory-residency rule does not apply — though domicile could still be examined separately.

Example 3 — resident by domicile below the threshold

Connecticut is your true, fixed, permanent home, but work sends you abroad and you spend only ~90 days in the state. You are under 183 days, yet you can still be taxed as a resident because your domicile remains in Connecticut.

Exceptions & edge cases

• Domicile overrides the day count. A Connecticut domicile makes you a resident below 183 days, unless one of the two domiciliary safe harbors applies; the day-count route is only one of two ways in.
• The abode must be genuinely permanent. A vacation-only camp or cottage, a motel room, or an apartment kept only for a fixed, limited assignment does not count, so more than 183 days alone need not trigger the rule.
• Armed forces. The statutory-residency route does not apply to a non-domiciliary on active service in the US armed forces.
• Credit for other states' tax. A resident taxed by another state on the same income may claim a credit, reducing double taxation even while remaining a Connecticut resident.
• Part-year moves. Moving into or out of Connecticut mid-year can create a part-year residency, changing how days and abode are assessed for the year of the move.

Common misconceptions

• "Under 183 days means I'm safe." False — a Connecticut domicile makes you a resident with any number of days.
• "More than 183 days always makes me a resident." Not on its own — the statutory route also requires a permanent place of abode in the state.
• "Only Connecticut income is taxed." A resident is taxed on worldwide income for the year, subject to a credit for tax paid to other states.
• "The 183 days must be one continuous stay." No — it is a running tally of every day of presence across the whole taxable year.

Frequently asked questions

Sources

• CT General Assembly — Chapter 229, Income Tax (Conn. Gen. Stat. § 12-701(a)(1))
• Regulations of Connecticut State Agencies — § 12-701(a)(1)-1, Resident of this state
• CT Office of Legislative Research — Residency for Tax Purposes (2020-R-0039)