Key takeaways
- File the CST-200CU in MyTaxes at mytaxes.wvtax.gov, and file it even when the period had no tax.
- Monthly and quarterly returns are due on the 20th, and the weekend rule moves a Sunday date to Monday.
- The statute allows quarterly filing at an average of $250 a month or less and annual filing at $600 a year or less.
- The November 2026 monthly return is due Monday, December 21, 2026, and the January 20, 2027 date covers the December monthly return, the fourth quarter return and the annual return.
- Municipal sales tax of up to 1% is collected by the state, so it belongs in the same return and the same client workpapers.
Where and how to file
The State Tax Department publishes the sales and use tax return as CST-200CU, and it is filed through the MyTaxes portal at mytaxes.wvtax.gov. Record in the engagement file whose login you use, so the next person knows how access works.
Special districts are the exception to the single return. Each district has its own form, listed on the department's sales and use tax page, and those returns can be filed in MyTaxes or mailed. The liquor and wine distribution return is CST-270, and the factory-built homes fee is FBH-100. If the client sells any of those, they are separate returns on the same calendar.
Put zero returns on the calendar for seasonal clients and file them, because a missed return is what creates a notice.
Rate and what the return reports
The general consumers sales and service tax is 6 percent. The statute states it as six cents on the dollar of sales or services, which is why you will see the combined figure on the return instead of a county rate table.
Build the sales report the way the return reads. Gross sales go in first, then each deduction or exemption with its own support, and the tax is computed from the taxable remainder. A single line labeled non-taxable sales on the client's ledger is the item most likely to be challenged, so split it into resale, exempt customer and out-of-state delivery before the period closes.
Filing frequency: what the statute allows
Monthly is the default. Under West Virginia Code 11-15-20, a taxpayer whose average monthly tax is $250 or less may file quarterly, and a taxpayer whose total tax for the year is $600 or less may file annually. The Tax Commissioner can change either threshold by legislative rule, so check the department's current guidance before telling a client to move.
A worked example: a client that collected $2,400 over the last twelve months averages $200 a month and qualifies for quarterly, while a client at $3,600 averages $300 and does not. An annual filer is capped at $600 of tax for the year, so one big December can push a client out.
I could not find a public page that explains how the department assigns a new account to a frequency, so treat the frequency shown in the client's MyTaxes account as the answer. Compare it with the trailing twelve months each January, and if the client has outgrown a lower frequency, move them up before the department does it for you.
Due dates through January 2027
Monthly and quarterly returns are due on the 20th of the following month. The State Tax Department's calendar shows CST-200CU for monthly and third quarter filers on October 20, 2026, and the same page lists CST-270, FBH-100 and the RTL special district returns on that date.
The calendar's weekend note says that if the due date falls on a Saturday, Sunday or legal holiday, the return may be filed on the first business day after. Applied to the rest of 2026, the October return is due Friday, November 20, and the November return is due on December 20, a Sunday, so it moves to Monday, December 21. The December 2026 return is due January 20, 2027.
The January calendar lists CST-200CU for monthly, fourth quarter and annual filers on one date, January 20. For tax year 2026 that means the December monthly return, the fourth quarter return and the annual return are all due on January 20, 2027, a Wednesday. The statute text for annual filers says thirty days after the end of the taxable year, which differs from the calendar line, so file annual clients by the January 20 date and do not rely on the longer reading.
Put an internal deadline on the 15th, not the 20th. A Sunday or holiday date moving to Monday is the only slack you get.
Municipal and special district tax
A West Virginia municipality may impose a sales and service tax at a rate not to exceed 1 percent, and the statute requires it to use the Tax Commissioner to administer and collect it. For you that means the municipal tax is reported with the state tax on the CST-200CU, not to the city. A new or changed municipal rate takes effect no earlier than the first day of a calendar quarter and at least 180 days after the city notifies the Tax Commissioner.
Check the client's location at the start of each quarter, because a rate change can only land on a quarter start. If the client delivers into other municipalities, ask for the delivery address of each taxable sale rather than the billing address.
Special districts work differently. In the Municipal Economic Opportunity Development Districts, the department states that the 6% state tax is replaced by a special district excise tax, and the 1% local sales tax remains. Those districts file on their own return by the 20th of the month after the sales occurred. A retailer in University Town Center, Charles Pointe, The Highlands or Park Place should expect an RTL return as well as the state one.
What a late return costs
West Virginia Code 11-10-18 adds 5 percent of the tax for failure to file if the failure is for not more than one month, plus 5 percent for each additional month or fraction, up to 25 percent. The addition for failure to pay is one half of one percent per month or fraction, also capped at 25 percent. Neither applies when the failure is due to reasonable cause and not willful neglect, and the filing addition is reduced by the payment addition for overlapping months.
A worked example: a client owes $2,000 for October and files and pays about six weeks after the November 20 due date. That is the second month counting fractions, so the filing addition is 10 percent, or $200, before the reduction for the payment addition, plus interest. File the return the day you find the miss even if the client cannot pay yet, because the filing addition grows ten times faster than the payment addition.
For a first-time lapse by a client with a clean history, write the abatement request around reasonable cause: what happened, the date it was found and the date it was fixed, with proof attached.
What to collect from the client each period
Ask for the same five items every month, on a fixed date, such as the 5th: the sales report by location, the deductions and exemption support, the resale and exemption certificates received, the bank deposit summary and any refunds or credit memos. Tie the sales report to deposits before the return is prepared.
For exemption certificates, ask for the certificate itself, not a note that the customer is exempt. Keep a log of customer, certificate date and the invoices it covers, and check it against the non-taxable total on the ledger.
Usual can run this as a recurring monthly request with a due date, upload fields for each item and automatic reminders, so the sales report and certificates arrive in one place. It does not file the return for you, so the CST-200CU still goes through MyTaxes.