Cascade Coffee Roasters' Washington return for November is due on Christmas Day itself, and switching from an S corporation to a C corporation would not move it by one day

The moment

Cascade Coffee Roasters roasts and sells wholesale coffee out of a warehouse in Tacoma, Washington. Mara Ostrander started it in 2015 selling five-pound bags to two cafes; eleven years later it supplies grocery chains and cafes across the Puget Sound region, with five people on payroll — two roasters, a green-bean buyer, a sales associate, and Mara herself — plus one delivery driver Cascade pays as a contractor rather than an employee. The business is taxed as an S corporation, an LLC election Mara's accountant set up in year three once the profit was steady enough to make it worth the paperwork.

It's the last week of September, and Mara is building next year's filing calendar the way she does every fall: one page, every date Cascade owes something to someone, taped inside the cabinet where the checkbook lives. Washington's own Combined Excise Tax Return — the one return that covers the state's B&O tax and any sales tax collected together — is filed monthly, assigned that way by the Department of Revenue when Cascade's wholesale volume crossed into the range that no longer qualifies for quarterly filing. Twelve returns a year, due, she has always assumed, "the 25th, same as always."

What they did instead

For three years running, Mara's bookkeeper wrote "excise return, 25th" on twelve lines of a calendar app and never looked past the number itself. Eleven of the twelve months in 2026 make that habit harmless — the 25th lands on an ordinary weekday. This year, building the calendar a full quarter ahead instead of month by month, Mara actually opened the Department's own 2026 due-date table rather than trusting the habit, and found the one month where "the 25th" and "an ordinary business day" come apart: the return covering November's activity is due December 25, 2026 — a day Cascade's own office is closed and the bookkeeper does not check email. Filing a day late over a forgotten holiday is a small, avoidable cost; finding it in September rather than in the last week of December is the entire difference.

The questions a CFO asks first

1. Across the whole year, does any Washington due date land on a day the office is actually closed, and how far ahead does that need to be caught?
2. Cascade's accountant has floated switching from an S corporation to a C corporation to make a future ownership change easier — would that move anything on the Washington side of this calendar?
3. If this year's own filing frequency question isn't answered before the calendar is built, does the tool guess a schedule, or say so plainly?
4. Since Washington taxes gross receipts rather than profit, does the entity question even reach the number Washington is actually taxing?

The arithmetic, shown

Three runs, all through the tool's own engine, all built on Cascade's actual profile: an S corporation, five W-2 employees, one 1099-NEC contractor, Washington added as the state, filing the Combined Excise Tax Return monthly.

Scenario one — the full year, run whole. The tool returns twenty-three dated line items. Four of them land on the same day, February 2, 2026: the Q4 2025 Form 941, the annual Form 940, the W-2 wage statements, and the 1099-NEC for the delivery driver — every year-end federal filing Cascade owes, due together before a single 2026 excise return is due at all. The twelve Washington returns themselves land on the 25th of the month following each reporting period, exactly as the Department's own general rule states, with one exception the tool computes rather than assumes:

> Washington Combined Excise Tax Return — November 2026 return

is due December 25, 2026 — not the 28th or the next weekday, the date Washington's own year-specific 2026 due-date table actually assigns, even though the Department's own general filing-frequency page states that a due date falling "on a weekend or legal holiday" is "extended to the next business day." The tool follows the Department's own resolved table over its own general rule, because the table is what the Department actually publishes for the year in question, not a formula this tool applied on top of it. The state's own two pages disagree with each other; the tool shows the one built for 2026 specifically, and says so.

Scenario two — the filing frequency not yet confirmed. Run with everything else answered but Washington's own excise filing frequency left blank, the tool does not guess monthly, quarterly, or annual on Cascade's behalf. It returns a named refusal: missing: ["how often Washington has this business file its Combined Excise Tax Return"]. Nothing about the Washington side of the calendar computes until an actual answer exists.

Scenario three — the same profile as a hypothetical C corporation. Running the identical facts with the entity question changed to a calendar-year C corporation returns twenty-four dated line items, not twenty-three — the federal side trades Cascade's four individual estimated-tax dates for a Form 1120 and four Form 1120-W deposits, a net gain of one date. But all twelve Washington Combined Excise Tax Return dates, including December 25, carry over unchanged, to the day, in both runs. The tool's own note says why before the arithmetic even has to prove it:

> Washington has no state personal income tax — Washington does not currently have an individual income tax. There's no state income-tax line in this calendar because there isn't one to invent. Its main business tax is the Business and Occupation (B&O) tax, a tax on gross receipts rather than profit: "Washington has a unique business tax structure. Most businesses in Washington are subject to a gross receipts tax known as business and occupation (B&O) tax. ... It is calculated on the total value of products sold or the total income the business earns. Because it is based on gross income, businesses cannot deduct expenses such as labor, materials, taxes, or other costs of doing business." That applies regardless of how this business is taxed for federal purposes, which is why nothing above about entity type changes what appears here.

What changed

Mara moved the prep work for the November-period return to the week before Thanksgiving instead of the last week of December, and put a second name on the reminder in case she is out that week too — a small change, made possible only by reading the actual 2026 table three months early instead of trusting three years of an unquestioned habit. When the accountant raised the C-corporation question again at the same meeting, the calendar answered it in one line: the Washington side of the business doesn't move, so whatever the entity decision turns on, it isn't this. None of this changed how much B&O tax Cascade actually owes on its gross receipts — this tool doesn't compute that figure at all — but it changed which twelve dates were guessed at and which twelve were confirmed, and it took one real argument for switching entities off the table before the accountant's meter started running on it.

What the tool will not do

It will not calculate the dollar amount of B&O tax Cascade owes on its gross receipts, this month or any month. It quotes the Department's own description of the tax — gross receipts, not profit, with no deduction for labor or materials — and stops there; the rate itself, which varies by the classification a business is assigned, is a number this tool does not compute.

It will not verify the volume or dollar threshold Washington uses to assign monthly, quarterly, or annual filing in the first place. Cascade's own letter from the Department already settled that question for this year; a business asking "will I be assigned monthly" gets no answer here.

It will not resolve the tension it found rather than smoothed over: the Department's own general rule says a due date lands on the next business day when it falls on a legal holiday, and the Department's own 2026 table still lists December 25 for November's return. This tool shows the year-specific table, not the general rule, and says plainly that the two pages disagree — it does not call the Department to ask which one actually governs a return filed a day late.

It will not know about Cascade's own extension, if one is ever filed, or about a payment plan or a penalty already assessed on any of these dates. This tool supports a named, growing list of states — Texas, Florida, Washington, Nevada, Wyoming, California, New York, South Dakota, Tennessee, Colorado, North Carolina, and Illinois as of this writing — and every line above is the plain, unmodified due date, not one adjusted for a fact only Cascade's own account with the Department would know.