The arithmetic of a seasonal hire is seductive because it fits on a napkin. You need more returns out the door. A seasonal preparer costs $25–40 an hour, when you can find one. Your realization on a straightforward 1040 is several times that. The gap looks like profit.
Then the season ends, and the napkin turns out to have left out four things. None of them are secrets. They're just easy not to count, because none of them arrive as an invoice.
The recruiting cost is yours, and it lands in the worst month
There is no HR department in a five-person firm. The partner writes the posting, screens the resumes, runs the interviews, checks the references, confirms the PTIN, and sorts the paperwork.
That happens in December and January — two months when partner attention is worth more than at almost any other point in the year. Engagement letters go out. Fees get reset. Organizers get sent. Every hour spent evaluating a candidate is an hour not spent on the decisions that set the profitability of the entire season.
And the yield is poor. Experienced preparers who want three months of work are among the most competed-for temporary labour in professional services. The good ones are booked by November, usually by the firm that had them last year. What's left in January is a thinner field than the napkin assumed.
The training curve is the wrong shape
The instinct is to treat training as a fixed setup cost — a week or two, then productivity. That's true for one category of work and false for the category you actually need help with.
A seasonal preparer can be genuinely productive on standard 1040s inside a fortnight. W-2 income, a mortgage, a couple of 1099s, your workpaper conventions, your software. Fine.
The returns clogging your extension pile are not standard 1040s. A Form 1116 with a carryover schedule. An FBAR scope decision on a client with signature authority over an employer's account. A part-year state allocation in a first year abroad. A K-1 that arrives in September with a foreign partner on it. Competence on that work is measured in seasons, not weeks — and a temporary preparer will never accumulate seasons, because they leave.
So you use them where they're safe. Which means seasonal help reliably increases your throughput on the returns that were never the problem.
The May cliff
The hire leaves in May. Not because anything went wrong — because that was the arrangement from the start.
By then, almost nothing in your extension pile is ready. The K-1s haven't arrived. The foreign wage statements haven't been translated. The client who is going to mention a Singapore account is going to mention it in September. The help arrived for the work you could already do, and left before the work you couldn't.
Everything they learned leaves with them. Your conventions, your clients' quirks, the workaround for the state that never e-files cleanly — all of it walks out and has to be rebuilt next January with a new person. You aren't building capacity. You're renting it, during the months you need it least, and paying the setup cost again every year.
The cost nobody puts on the timesheet
Here is the item that breaks the napkin entirely: adding a preparer does not add a reviewer.
Every return a seasonal hire touches comes back to the same desk — the partner or the senior reviewer, the genuine constraint in the building. On familiar work that review is quick. On unfamiliar work it isn't review at all; it's re-preparation with a second signature on the end. The reviewer rebuilds the logic in order to check the logic.
So the seasonal hire converts a preparation bottleneck into a review bottleneck. Review is the more expensive of the two, performed by the more expensive person, and it is the one thing a junior hire structurally cannot relieve.
This is why so many small-firm partners end up preparing the hard returns themselves, at night, in October. It isn't stubbornness or poor delegation. It's the only version of the workflow where the return gets touched once.
What outside capacity has to do to actually help
Three things have to be true, or you've simply moved the bottleneck.
It has to exist in August, September and October. Capacity that is available January through April solves the part of your year that was already working.
It has to be expert in the work you aren't. A return your practice sees twice a year is a return somebody else sees twice a week. That asymmetry is the entire source of the efficiency — not cheaper hours, but hours spent by people who don't have to re-learn the form.
It has to arrive reviewed. This is the one firms underweight. Work that lands on your reviewer's desk unfinished is not capacity; it's homework. If a second credentialed set of eyes has already checked the return before you see it, your partner hour goes back to being what clients actually pay a partner for — judgment and sign-off.
Buying an hour versus buying a return
That last point is also where the two pricing models diverge, and it's worth being blunt about it.
When you buy an hour, you buy effort. The risk of a return taking three times as long as it should sits with you, and so does the cost of checking it. When you buy a return at a flat price, you know the cost before you commit, the overrun is somebody else's problem, and the review is part of the cost of goods rather than part of your October.
Set the two side by side honestly. Seasonal preparer: recruiting in December, training through February, useful in March and April, gone in May, retrained next year — and every return still passing through your reviewer. Outside preparation priced per return: no recruiting, no training, available exactly when the pile is, reviewed before it reaches you, and gone again the moment you don't need it.
One of those scales with your April. The other scales with your October.
You already know which one is on your desk right now.