Padda v. Commissioner: winning by significant participation

By Max Medvedev · 6 Aug 2026

Padda v. Commissioner, T.C. Memo 2020-154, is a taxpayer win on the least-used route through Reg. §1.469-5T(a): the significant participation activity test. More than 100 hours in each of several activities, adding to more than 500 hours across them, is material participation — even where no single activity would clear 500 on its own.

What happened

The taxpayers held several activities. In each one they participated for more than 100 hours, and the total across those activities exceeded 500 hours. That combination is test 4 of the seven material participation tests, and it carried the case. They won.

The reported lesson is the route itself. Most writing about short-term rentals treats the choice as two options — more than 500 hours in the activity, or more than 100 hours and more than any other single individual — and stops there. Padda is the case that shows the fourth test is not decorative. It has real work to do for an owner whose time is split across more than one thing.

What the court held

Test 4 has two conditions, and both are exact.

First, each activity has to be a significant participation activity: the owner puts in more than 100 hours there, and does not materially participate in that activity under any of the other tests taken alone. That definition sits in Reg. §1.469-5T(c). An activity where the owner already clears 500 hours, or already beats every other individual, is not an SPA — it passed on its own and never enters the pool.

Second, the total SPA hours across all of them must exceed 500. When that holds, material participation is established in each activity in the pool.

The consequence is the interesting part: test 4 has no "more than anyone else" leg. A property where a cleaner or manager out-hours the owner can still be a significant participation activity, because the comparison that decides test 3 never runs here. Two or three properties at 180 hours each get to 540, and the pool carries all of them.

One boundary applies before any of that. An SPA has to be a trade or business activity — Reg. §1.469-5T(c)(1)(i), within the meaning of Reg. §1.469-1T(e)(2). A rental activity that has not escaped the rental label through the seven-day average-stay exception or the 30-day-with-services route is passive per se under §469(c)(2) no matter how the hours look. It neither joins the pool nor passes test 4 by itself. The classification math comes first, always: average stay is nights divided by reservations, computed per property.

The tell

The tell in Padda is attribution. Test 4 is the one route where pooled hours are worthless.

Every other test asks a single question about a single activity. Test 4 asks the same question several times, then adds the answers — and each activity has to clear its own 100-hour floor before its hours are allowed into the total. A record showing "540 hours across the portfolio" proves nothing at all under this test. A record showing 190, 175 and 175 hours attributed to three named activities proves everything.

That is a recordkeeping requirement disguised as a math rule. It means every entry has to name which activity it belongs to at the moment it is written, because that attribution cannot be reconstructed later without becoming exactly the sort of after-the-fact allocation courts reject. Sezonov, T.C. Memo 2022-40, dismissed rebuilt hours as "ballpark guesstimates," and Moss v. Commissioner, 135 T.C. 365 (2010), had already held the regulations "do not allow a post-event ballpark guesstimate." Splitting a year's shared work between two properties in April is that same act with a spreadsheet formula on top.

What this means for your records

The rule that falls out: hours are logged per activity, or test 4 is not available.

Three practical consequences ride on it.

Each entry names its property when it is written, not at filing time. Work genuinely spanning two properties gets split as it happens, with the outside record — the invoice, the message thread, the receipt — attached to the side it belongs to.

Each property still needs its own classification. Grouping under Reg. §1.469-4 is a different instrument entirely: it merges activities into one activity by an election attached to a timely filed original return, is generally binding until a material change, and alters what a later sale of a single property releases. Test 4 aggregates hours without any election at all. Confusing the two produces a filing position nobody can defend.

And the win comes with a tail. Where material participation is met only through test 4, a special recharacterization rule under §1411 can still pull the income back into net investment income and its 3.8% surtax. That does not undo the participation result, but it changes what the result is worth. Where an owner can reach test 1 (more than 500 hours in the activity) or test 3 (more than 100 hours and more than any other single individual), those are the stronger positions.

A log kept as the work happens carries all three of these without extra effort, because the attribution, the date and the evidence go in together. Here, the per-property hours feed each test separately, the SPA pool is assembled from properties that clear 100 hours on their own, and a pass that rests only on the SPA route is flagged with the §1411 consequence attached, so the route that won the year is never a surprise at the end of it.

Where this fits

Padda widens the door for owners with more than one property, and narrows the record that fits through it. The other tests, and what counts toward them, are in the hub guide on how to prove short-term rental hours.

To see which route a specific year actually passes on, run the properties and hours through the estimator — it evaluates all seven tests in Reg. §1.469-5T(a) per property, assembles the significant-participation pool, and cites the rule behind every number.