Now tracking 315 jurisdictions

Know exactly where you stand.

Tax Days tracks your days against the residency rules that matter — US states, the federal Substantial Presence Test, Schengen 90/180, the UK SRT, and more — so a single missed day never costs you thousands.

Download Tax Days on the App StoreSee how it works ↓
Jurisdictions
315
Per year
$19.99
Free trial
7 days
Tax Days home screen showing real-time residency status across multiple jurisdictions

Why Tax Days

US + International, in one app

State residency, federal SPT, Schengen 90/180, UK SRT, and more. The first tracker that does both well.

Trip-based, not GPS

Log arrivals and departures. No battery drain, no missed days, no tracking you while you sleep.

Audit-ready records

Contemporaneous day counts, exportable to PDF and CSV. Defensible if your state ever asks.

How it works

Three steps from blind
to bulletproof.

  1. 01

    Pick your jurisdictions

    Choose from 315 states, countries, and tax regions — from New York and California to Schengen, the UK, and the federal Substantial Presence Test.

    Tax Days settings screen showing supported jurisdictions and rules
  2. 02

    Log every trip on a single calendar

    Tap any date to add a trip. Color-coded days. Conflicts flagged automatically. Your entire travel year, at a glance.

    Tax Days calendar screen with trips highlighted across months
  3. 03

    Always know where you stand

    Real-time dashboard. Smart projections. Notifications at 30, 14, 7, 3, and 1 days before any threshold.

    Tax Days dashboard with rule progress bars for multiple jurisdictions
Features

Every rule that matters,
in one beautiful app.

Real-time residency dashboard

Every rule on one screen. Traffic-light status. Days used, days remaining, days projected — at a glance.

Tax Days dashboard with rule progress bars

A calendar that thinks in trips

Color-coded days, tap-to-add simplicity, and conflicts flagged automatically. Your entire travel year, at a glance.

Tax Days yearly calendar with trips highlighted

Schengen 90/180, finally readable

Rolling 180-day window. The exact day you'd hit 90 if you stay. No more spreadsheet math, no more anxious math at the airport.

Tax Days Schengen 90/180 rolling-window detail

Smart alerts before you cross

Configurable warnings at 30, 14, 7, 3, and 1 days before any threshold. Set it once. Stop worrying.

Tax Days notification settings screen

Year-over-year stats

Days per jurisdiction, trip insights, year comparisons. Spot patterns before your accountant does.

Tax Days stats screen with annual summary and per-rule status

Private by default

No servers. No accounts. iCloud-synced and on-device only. Your travel data stays yours — always.

Tax Days settings showing supported jurisdictions and rules
315 jurisdictions

State residency. Federal SPT.
Every 183-day rule.

Tax Days knows the difference between New York's 184-day rule and California's facts-and-circumstances test. Each jurisdiction has its own threshold, its own tax year, and its own definition of a “day”. Tax Days handles them all.

  • New York · 184 days
  • California · 9-month safe harbor
  • Florida · 183-day domicile
  • Texas · domicile
  • Illinois · 9-month presumption
  • New Jersey · 183-day
  • Substantial Presence Test
  • Schengen Area · 90/180
  • United Kingdom · SRT
  • Canada · 183-day
  • Australia · 183-day
  • Germany · 183-day
  • France · 183-day
  • Spain · 183-day
  • Italy · 183-day
  • Portugal · NHR
  • Netherlands · 183-day
  • Switzerland · 90-day
  • UAE · 183-day
  • Singapore · 183-day
  • Japan · 183-day
  • Mexico · 183-day
  • …and 290 more
Why Tax Days

Counting days
shouldn't cost
you five figures.

Every other tracker is either too clunky to use, too expensive to justify, or too narrow to cover the way people actually travel. Tax Days is what every accountant has been waiting for their clients to download.

A progress bar showing 142 of 183 days used in New York

A single missed day costs more than a decade of Tax Days.

New York collected $3 billion from residency audits in 2022–23. One state filing mistake can cost five figures. Tax Days is $19.99 a year — about the price of two coffees a month.

The only app that handles US states *and* the world.

TaxBird does US states. Schengen calculators do Schengen. Monaeo does enterprise. Tax Days does all of it — in one beautifully designed app, on the device you actually carry.

Trip-based by design. Battery, privacy, and accuracy intact.

GPS trackers drain your battery, leak your location, and miss days when the signal drops. Tax Days asks for arrivals and departures — the same way your CPA does — and the math just works.

Pricing

One hour with a tax attorney
costs $300+. Tax Days is $19.99/yr.

A single state filing mistake can cost thousands. Tax Days is cheaper than the consultation you'd need to fix it.

Comparison of Tax Days against TaxBird, Domicile365, and Monaeo
FeatureTax DaysTaxBird
Annual price$19.99$40
Trip-based (no GPS drain)✓—
US state rules✓✓
International rules✓—
Schengen 90/180✓—
Smart projections✓—
iCloud sync✓—
Audit-ready PDF/CSV export✓—

Free

$0

Up to 5 trips per year, 1 active rule, 2 jurisdictions. Try the dashboard and calendar — no card required.

Pro Monthly

$2.99/mo

Unlimited trips, unlimited jurisdictions, notifications, iCloud sync, smart projections, and full export.

Best value

Pro Annual

$19.99/yr

Just $1.67/month. 7-day free trial. Everything in Pro Monthly, billed once a year.

Download Tax Days on the App Store7-day free trial · Cancel anytime · iPhone, iPad, and Mac
Questions

What people ask

How is Tax Days different from TaxBird, Domicile365, or Monaeo?

Tax Days is the first app that combines US state, US federal, and international tax residency rules in one place — at $19.99/year. TaxBird is US-only and GPS-based (battery drain, missed days). Domicile365 is $240/yr with dated UI. Monaeo is enterprise pricing. Tax Days gives you trip-based tracking, beautiful design, and every rule that matters.

What's the 183-day rule, exactly?

Most jurisdictions consider you a tax resident if you spend more than 183 days in a calendar (or tax) year there. The exact threshold and how a 'day' is counted vary — New York counts any part of a day, Schengen uses a rolling 180-day window, and the federal Substantial Presence Test uses a 3-year weighted formula. Tax Days handles all of these.

Does Tax Days track me with GPS?

No. Tax Days is trip-based: you log arrivals and departures, and the app calculates your day counts. This is more accurate, more private, and better for your battery than GPS-based competitors. Auto-tracking via location is available as an optional Pro feature.

What jurisdictions does Tax Days support?

315 jurisdictions including US states (NY's 184-day + abode rule, CA's 9-month safe harbor, FL, TX, IL, NJ, and more), the federal Substantial Presence Test, Schengen 90/180, the UK Statutory Residence Test, and a configurable 183-day rule for any country.

Is Tax Days suitable for an audit?

Yes. Tax Days produces contemporaneous, exportable records (PDF and CSV) showing your trips and day counts. These are the kind of records tax authorities expect to see in a residency audit. Tax Days is not legal or tax advice — but it gives your CPA exactly what they need.

Will my data sync across my devices?

Yes — via your private iCloud container. Your trip data is stored on-device and synced through iCloud. We never see it. Tax Days has no servers, no accounts, and no analytics on your travel data.

How much does Tax Days cost?

Tax Days Pro is $19.99/year (with a 7-day free trial) or $2.99/month. There's also a free tier with up to 5 trips per year, 1 active rule, and 2 jurisdictions — plenty for trying out the app.

Is Tax Days iOS only?

Yes — Tax Days is a native iPhone app, with iPad and Mac (Catalyst) support included for Pro users via iCloud sync.

Who is Tax Days for?

Snowbirds splitting time between New York and Florida. Remote workers hopping between states. International travelers tracking the Substantial Presence Test. Digital nomads watching their Schengen days. Expats. Anyone whose accountant said "you need to start tracking your days."

Ready to count

Your days count.
Now you can count them back.

Stop doing tax math on napkins, in spreadsheets, or worse — in your head. Tax Days does it the moment you log a trip, and warns you before any of it costs you money.

Every rule that matters

315 jurisdictions, including all US states, the SPT, Schengen, UK SRT, and more.

Real-time status

Traffic-light dashboard. Smart projections. Notifications before you cross.

Audit-ready

Contemporaneous records, exportable to PDF and CSV. Defensible if asked.

$19.99 a year

Less than the consultation you'd need to fix a single missed day.

Download Tax Days on the App Store7-day free trial · iPhone, iPad, Mac · Your data stays yours