For a calendar-year short-term rental owner the sequence is: October 15, 2026 for 2025 returns on extension, December 31, 2026 when the 2026 tax year and its hours close, January 15, 2027 for the final 2026 estimate, April 15, 2027 to file or extend the 2026 return, and October 15, 2027 for that extension. Under IRC §7503 a due date that falls on a Saturday, Sunday or legal holiday generally moves to the next business day. None of the main dates below need that shift, but the IRS publishes the authoritative calendar on irs.gov and dates are worth confirming there before anyone relies on one.
The reason an hours log belongs on this calendar is that two of these dates are hard stops for the record itself, and the rest are the days someone asks to see it.
October 15, 2026: 2025 returns on extension
A Thursday. Anyone who filed Form 4868 in April has until this date to file the 2025 Form 1040. If 2025 was the first year a short-term rental loss was claimed against other income, the 2025 hours log is the document supporting that position, and a preparer finishing the return this week may still be asking questions about it.
Two things worth knowing about the extension: it extended the filing date, not the payment date, so interest on a 2025 balance generally runs from April 15, 2026. And once the return goes out, the 2025 log should be closed — exported, filed, and not edited afterwards. A log that keeps changing after the return is filed is a log with no fixed version to point to.
December 31, 2026: the year closes on your hours
A Thursday, and the most important date on this list for record-keeping. Material participation under Treas. Reg. §1.469-5T is measured over the taxable year. Hours worked on January 2, 2027 count toward 2027, however close a property came to a threshold in 2026.
Two numbers are fixed at year end and cannot be improved later:
- Your participation hours for each activity in 2026 — and, if the property relies on the 100-hour test in §1.469-5T(a)(3), each other individual's hours as well. A cleaner's or co-host's time is part of that comparison.
- The average period of customer use for each property, which determines whether §1.469-1T(e)(3) treats it as a rental activity at all. That figure is a function of the bookings, not of anything written in a log, so it is checked on the booking platform.
Late December is the last useful window for work an owner genuinely intends to do anyway — a deep clean, deferred maintenance, the listing rewrite that has been waiting since August. It is not a window for writing down hours that were not worked. The year-end hours checklist sets out the review in order.
January 15, 2027: the fourth-quarter estimate
A Friday. The final estimated tax payment for the 2026 tax year is generally due on this date for taxpayers who pay estimates, using Form 1040-ES. Whether a short-term rental loss changes that payment depends on the participation position the return will take, which is one more reason to have December's totals settled before this date rather than in March.
Late January 2027: platform statements and contractor forms
January 31, 2027 is a Sunday, so forms due that day generally move to Monday, February 1, 2027. Two of them reach hosts.
- Form 1099-K from booking platforms and payment processors. Compare the gross figure against your own records before it reaches a return — platform gross generally includes amounts that were never yours to keep, such as cleaning fees paid straight out again and taxes the platform collected.
- Form 1099-NEC, where a cleaner, handyman or co-host was paid as an independent contractor and the payments reach the reporting threshold. Whether a filing obligation exists is a question for your preparer.
Those contractor records have a second job. The invoices behind them are the corroboration for the other-participants hours the 100-hour test turns on, which is why they are worth keeping with the log rather than only with the bookkeeping.
March 15, 2027: partnerships and S corporations
A Monday. Calendar-year Form 1065 and Form 1120-S returns for 2026 are due, along with the Schedule K-1s that feed individual returns. An owner holding a short-term rental through a multi-member LLC is on this date for the entity return, not April's.
Material participation is still tested at the individual level in that structure. IRS Publication 925 describes how the passive activity rules apply to an interest held through a pass-through entity, and each member's own hours record still has to exist independently of the entity's books.
April 15, 2027: file or extend
A Thursday, with no weekend shift this year. The 2026 Form 1040 is due, or Form 4868 for an extension to October 15, 2027. The first 2027 estimated payment is generally due the same day.
By this date the 2026 log should be a finished document rather than a working file. STR Tracker exports any date range — a quarter, a closed tax year, a single property — as a dated PDF or spreadsheet, which is what makes it possible to hand over a version and know exactly what was in it. What to send your CPA covers the rest of that package.
Later in 2027
- June 15, 2027 (Tuesday): second 2027 estimated payment.
- September 15, 2027 (Wednesday): third 2027 estimated payment, and extended 1065 and 1120-S returns.
- October 15, 2027 (Friday): extended 2026 individual returns, where an extension was filed in April.
State income tax filings, and the lodging or occupancy tax returns most short-term rentals owe, run on separate calendars — often monthly or quarterly, and unaffected by everything above. Those are usually the deadlines a first-year host misses, because nothing on the federal calendar hints at them.
What the log needs at each date
| Date | The record-keeping step |
|---|---|
| Oct 15, 2026 | Close and export the 2025 log; stop editing it |
| Dec 31, 2026 | Final 2026 entries in; other participants' hours updated; average stay checked on the platform |
| Jan 15, 2027 | 2026 totals per property settled so estimates are not guesswork |
| Feb 1, 2027 | 1099-K reconciled to your own figures; contractor invoices filed with the log |
| Mar 15, 2027 | Individual hours separated from entity bookkeeping |
| Apr 15, 2027 | 2026 log exported as a dated document and handed over |
| Oct 15, 2027 | The 2027 log already nine months old, not nine months of memory |
Common mistakes on this calendar
The first is treating April as the month the log gets written. A reconstruction assembled from platform messages and receipts in April is not contemporaneous, and the Tax Court has consistently cared more about when a record was made than how many hours it shows.
The second is assuming an extension buys time to keep accumulating hours. It does not. The taxable year closed on December 31 regardless of when the return goes out.
The third is letting the average-stay question wait until filing. If a property's bookings put its average period of customer use above seven days, the analysis under §1.469-1T(e)(3) changes, and finding that out in April is worse than finding it out in October while there is still a booking calendar to look at.
None of this is complicated once it is on a calendar. Pick the two dates that fix the record — December 31 and whichever filing date applies — and work backwards from them. Start logging the hours as they happen so that neither date comes as a surprise.