Cumberland Strings has nine Tennessee sales-tax dates on its sheet and three missing, and the biggest Tennessee tax is not on it

The moment

Cumberland Strings is a guitar and banjo shop in Franklin, Tennessee: new instruments, used ones on consignment, strings, repairs and a back room for lessons. Reggie Tolliver opened it in 2016. It has three W-2 employees besides Reggie, it is taxed as an S corporation, and it collects Tennessee sales tax at the counter. It is the third of October, the holiday rush is five weeks off, and Reggie is putting next year's dates on the office wall.

What they did instead

Reggie's habit was the 20th. Sales tax, the 20th, every month, filed from the bank-balance screen when the account looked healthy. That works in nine months out of twelve in 2026. It fails in three, because June 20 is a Saturday and September 20 and December 20 are Sundays. Nothing on the Department's pages tells Reggie which way those go. The cost of a wrong guess is a late return on a tax the shop has already collected from customers, which is money that was never the shop's to hold.

The questions a CFO asks first

1. How many Tennessee dates does the shop have in the next year, and does any of them share a day with something else?
2. What does the Department say about a due date that lands on a weekend?
3. What changes if Tennessee has the shop on a quarterly or annual schedule?
4. Tennessee has no personal income tax. Does that mean the shop has no other Tennessee tax?

The arithmetic, shown

Seven engine runs, all through the tool's own engine, all built on Cumberland's profile: an S corporation, three W-2 employees, no 1099 contractors, Tennessee as the state, registered to collect Tennessee sales tax.

Scenario one: monthly, the schedule the shop is on. The Department of Revenue's due-dates page states

> Monthly - 20th day of the month following the end of the reporting period. Quarterly - 20th day of the month following the end of the quarter (January 20, April 20, July 20, October 20). Annually - January 20.

The tool returns nineteen dated line items. Nine are Tennessee sales-tax returns, dated the 20th of January, February, March, April, May, July, August, October and November 2026: 2026-01-20 first and 2026-11-20 last. The other ten are federal: the owner's four estimates, four Form 941 payroll returns, Form 940 and the W-2s. There is not one Tennessee estimated-tax line, and the tool says why:

> There's no state income-tax line in this calendar because there isn't one to invent, and that's true regardless of how this business is taxed for federal purposes.

Twelve months of returns would be twelve dates. The tool gives nine. June 20 is a Saturday, and September 20 and December 20 are Sundays. The tool does not move them to Monday and does not print them. It says

> Every other state in this tool has a stated shift rule; Tennessee, so far, does not — check with the Department directly for those three months' actual due dates rather than assume the common rule applies.

That is a sharper choice than South Carolina's, where the three weekend dates stay on the sheet as published with a question mark. Here they are gone. A Tennessee sheet with nine returns on it is not a sheet with nine returns due. It is a sheet with three months the owner has to settle with the Department.

One more gap, and the note does not mention it. The sheet stops at 2026-11-20. The return for December sales would be due in January 2027, and the tool carries no Tennessee date in 2027 on any schedule.

The crowding is none. Each of the nine Tennessee dates is the only item on its day. The federal dates sit on other days: February 2 carries three items, the fourth-quarter Form 941, Form 940 and the W-2s, and April 15, June 15 and September 15 each carry the owner's federal estimate on its own.

Scenario two: quarterly. The tool returns thirteen items, not nineteen, with three Tennessee returns dated 2026-04-20, 2026-07-20 and 2026-10-20. All three are weekdays, so the weekend note does not appear. The fourth return, due January 20, 2027, is not listed, and the tool says

> The Q4 2026 quarterly return (due January 20, 2027) isn't listed — this run only checked 2026 dates, which doesn't cover January 2027 yet.

Scenario two (b): annual. The tool returns eleven items and one Tennessee return, dated 2026-01-20. That date has passed. It is the 2025 annual return. The 2026 one, due January 20, 2027, is not listed:

> The 2026 annual return (due January 20, 2027) isn't listed — this run only checked 2026 dates, which doesn't cover January 2027 yet.

Scenario two (c): a schedule the tool does not date. If the shop is on something else, or is not sure, the tool returns ten items: the federal ones and no Tennessee date. It says

> This tool doesn't compute a specific date for a Tennessee sales-tax filing frequency other than monthly, quarterly, or annual, or one that isn't confirmed.

and prints the Department's rule with a pointer to its page.

Scenario three: the frequency not yet confirmed. With everything else answered and the filing frequency left blank, the tool does not guess. It returns a named refusal: missing: ["how often Tennessee has this business file sales tax"]. Nothing computes until there is an answer.

Scenario four: the identical profile as a calendar-year C corporation. The tool returns twenty items, not nineteen. Federal Form 1120 and four Form 1120-W deposits arrive in place of the owner's four estimates. The nine Tennessee returns do not change, because Tennessee's calendar here is the sales-tax return and nothing else. Entity type moves no Tennessee date.

Scenario four (b): the same corporation, tax year unconfirmed. Mark the tax year as not calendar-year, or as unconfirmed, and the tool returns fifteen items. The five corporate federal dates vanish. The nine Tennessee returns stay.

What changed

Reggie has nine Tennessee dates on the same sheet as the federal payroll and estimated-tax dates, and no Tennessee date crowds another. The numbers to watch are three and one: three months the tool left off because the weekend rule is unwritten, and one tax the sheet does not mention. The nine are the ones to put on the wall. The three go on a list for the Department, with the question written out.

What the tool will not do

It will not decide which schedule the shop is on. The Department assigns it, so the tool asks and builds dates from the answer. It will not compute the tax owed on any return. And for Cumberland specifically, the sheet is shorter than the real year. The tool's own note says what is off it:

> This tool doesn't cover Tennessee's Franchise & Excise Tax (a tax on net worth and net earnings that reaches most LLCs and corporations, but not sole proprietorships) or its separate Business Tax (a gross-receipts tax collected at the state and local level) — this run only verified the sales-tax rule below.

The Department lists both on its own tax page, next to sales tax. Cumberland is an S corporation. Tennessee having no personal income tax does not mean a corporation owes the state nothing but sales tax, and the sheet's missing Tennessee income line is no sign that nothing else is due. The tool does not know whether Cumberland owes either one, or when. It will not know about an extension, a payment plan or a penalty already assessed on any date above. This tool supports a named list of states, which the state picker in the tool shows, and every line above is the plain due date for the entity type it was told about.