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Tax residency guides for the
183-day rule, SPT, Schengen & more
Plain-English explanations of the rules that decide where you owe tax. Written for individuals, not corporate tax departments.
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- Guides12 min read
Defending a residency audit: timeline, evidence, and what auditors actually do
State residency audits target high-earners who claim to have left. Here's what to expect, the timeline, the evidence requests, and how to defend your domicile and day count.
Read the guide → - Federal9 min read
Form 8840 and the closer-connection exception
Even if you meet the IRS Substantial Presence Test, you can avoid US tax-resident status by claiming closer connection on Form 8840, but only if you meet specific day-count and residency conditions.
Read the guide → - Federal11 min read
The SPT 3-year weighted formula, with worked examples
The IRS Substantial Presence Test uses a 3-year weighted day-count formula. Here it is in plain math, with multiple worked examples for visa types and travel patterns.
Read the guide → - Guides6 min read
Tax Days vs. Topia: a comparison for individual cross-border residents
Topia is enterprise mobility software for global employers. Tax Days is for individuals. Here's why the comparison matters and which is right for you.
Read the guide → - Guides11 min read
The remote worker's multi-state tax guide: nexus, day counts, and double tax
Working remotely from multiple states triggers state nexus, withholding obligations, and potential double taxation. Here's how to track days, manage employer obligations, and avoid surprise tax bills.
Read the guide → - Guides7 min read
Tax Days vs. Domicile365: feature, price, and privacy comparison
Domicile365 is a long-running residency-tracking service for snowbirds and cross-border workers. Tax Days is the iPhone-native alternative. Here's how they compare.
Read the guide → - US States9 min read
Pennsylvania residency rules: domicile, statutory residence, and Philly's local tax
Pennsylvania has a 3.07% flat tax, but Philadelphia adds a 3.75% city wage tax. Here's how PA's domicile test, statutory residence rule, and local tax interact for departing residents.
Read the guide → - Guides7 min read
Tax Days vs. iReside: which residency tracker is right for you?
iReside and Tax Days both target privacy-conscious, internationally-mobile users. Here's an honest comparison on price, tracking method, jurisdictions, and privacy.
Read the guide → - US States9 min read
Illinois residency rules: domicile, the abode test, and Chicago tax exposure
Illinois taxes residents at a flat 4.95%. Combined with Chicago's lifestyle tax exposure, the move to Florida is popular among Chicago-area professionals. Here's how Illinois residency really works.
Read the guide → - Guides12 min read
The expat day counter guide: residency, treaties, and the rules you'll actually face
If you're an American living abroad, a Brit in the EU, or anyone with a foreign tax home, day counts decide where you owe tax. Here's the playbook for tracking residency thresholds and treaty tie-breakers.
Read the guide → - Guides7 min read
Tax Days vs. TaxBird: which residency tracker is right for you?
TaxBird and Tax Days both target snowbirds and cross-border residents. Here's an honest comparison on price, jurisdictions, GPS, privacy, and audit support.
Read the guide → - Guides8 min read
Tax Days vs. Monaeo: an honest comparison
Monaeo is a long-running residency tracker for high-net-worth individuals at $1,200+/year. Tax Days is a privacy-first iPhone app at $19.99/year. Here's how they compare on jurisdictions, accuracy, and what each does best.
Read the guide → - US States10 min read
West Virginia's 183-Day Rule & the 30-Day Exit: Residency Both Ways
West Virginia's 183 day rule catches non-domiciliaries with a home in-state, while leavers can only break residency through a strict 30-day domicile safe harbor.
Read the guide → - Guides12 min read
How Snowbirds Should Track Tax Days: US States and the US-Canada Border
Snowbirds cross two very different borders for tax: the US state line and the US-Canada border. How to count days for each, the forms that protect you, and the app that keeps the record.
Read the guide → - US States10 min read
Oklahoma's Seven-Month Residency Rule: Months, Not 183 Days
Oklahoma generally presumes you're a resident if you spend more than seven months of the year in-state. The statute is written in months, not 183 days, and the presumption is rebuttable.
Read the guide → - US States10 min read
North Dakota's 7-Month (210-Day) Residency Rule: A High Bar for Snowbirds
North Dakota's residency test taxes you as a resident if you keep a permanent home there and spend more than seven months (210 days) in-state, a higher bar than the usual 183 days.
Read the guide → - US States10 min read
New Mexico's 185-Day Rule: Why Only Full 24-Hour Days Count
New Mexico taxes you as a resident if you're physically present 185 days or more, but only full 24-hour days count. Partial arrival and departure days generally don't.
Read the guide → - US States10 min read
Nebraska's 183-Day Residency Rule: Permanent Abode & Any-Part-of-a-Day Counting
Nebraska taxes you as a resident if you keep a permanent place of abode there and spend more than 183 days in-state, and any part of a day generally counts as a full day.
Read the guide → - US States10 min read
Kentucky's 183-Day Rule & Reciprocity: A Cross-Border Commuter's Guide
Kentucky generally treats you as a resident at over 183 days with a home in-state, but reciprocity with seven neighbors keeps cross-border wages taxed only at home.
Read the guide → - US States10 min read
Iowa's 183-Day Rule: A Rebuttable Presumption You Can Fight
Iowa presumes you maintain a permanent place of abode there if you keep an Iowa home and pass 183 days in-state. It's rebuttable, but the burden shifts to you.
Read the guide → - US States10 min read
Indiana's 183-Day Residency Rule, Domicile & Reciprocity Explained
Indiana taxes you as a resident if you keep a permanent home and spend over 183 days in-state, or if you're domiciled there. Plus how reciprocity works for KY, MI, OH, PA, and WI commuters.
Read the guide → - US States10 min read
Hawaii's 200-Day Rule: The Rebuttable Presumption of Residency
Hawaii presumes you are a resident if you spend more than 200 days there in a tax year. It is a rebuttable presumption: how it works and how to overcome it.
Read the guide → - US States10 min read
Washington DC's 183-Day Residency Rule: The Abode-Maintained Trap
DC taxes you as a statutory resident if you maintain a place of abode in the District for 183 days or more, a count that can include temporary absences, not just physical presence.
Read the guide → - US States10 min read
Arkansas' Six-Month Residency Rule: Home Plus More Than Six Months
Arkansas treats you as a resident only if you keep a permanent home there and spend more than six months in-state. Both conditions are required, and the rule is months-based.
Read the guide →