To remit sales tax, you file a return with each state where you’re registered and transfer the tax you collected from customers during the reporting period, using the state revenue department’s online portal by the deadline tied to your assigned filing frequency. The money you collected isn’t revenue. It’s held in trust for the state, and most jurisdictions can pursue the individuals who run the business personally if it isn’t paid over.
Register Before You Collect
You can’t legally collect or remit sales tax without a permit from the state. Different states call it a seller’s permit, a sales tax license, or a certificate of authority, but they all do the same thing: open a tax account in your business’s name so the state can match your filings and payments. Most states issue permits for free through an online application. A few charge up to $100, and some require a refundable security deposit or surety bond at registration.
The permit number appears on every return you file. Without it, the state has no way to credit your payment. Collecting sales tax from customers without a valid permit is treated as a serious offense in every state that imposes the tax, with penalties running from steep fines to forced closure. Apply before your first taxable sale, not after.
Know Your Filing Frequency and Due Date
States assign each business a filing frequency of monthly, quarterly, or annual based on how much sales tax it collects. Higher-liability businesses file more often because the state wants access to the money sooner. Businesses collecting more than a few hundred dollars a month are almost always assigned to monthly filing; smaller collectors may qualify for quarterly or annual.
Your assigned frequency is set when you register, and the state can change it. Most revenue departments re-evaluate annually against your recent liability, so a quarterly filer with a strong year can be moved to monthly.
Returns are generally due by the last day of the month following the reporting period. A January return would typically be due at the end of February. If that date falls on a weekend or state holiday, the deadline moves to the next business day. The deadline covers both the return and the payment. Filing on time but paying late still triggers penalties.
Calculate What You Owe
Every return starts with total gross sales for the period, including transactions that aren’t taxable. From that figure you subtract exempt sales to reach your net taxable amount. The state’s return form walks through these subtractions, and most portals do the arithmetic for you.
Common exemptions include sales to nonprofits, items bought for resale, and categories a state has chosen to exempt such as groceries or prescription drugs. Each exemption needs supporting documentation. A resale exemption only holds up if you have the buyer’s resale certificate on file; without it, you owe the tax on that sale regardless of what the buyer intended to do with the goods. Many states publish an online lookup tool that lets you verify a customer’s exemption certificate when you first accept it. That check is far easier now than reconstructing paperwork during an audit years later.
You then apply the applicable tax rate to the taxable amount. The rate isn’t always a single number. State, county, and city rates can stack, and the population-weighted national average comes to about 7.5% when all layers are combined, ranging from zero in the five states without a sales tax to over 10% in the highest jurisdictions.1Tax Foundation. State and Local Sales Tax Rates, 2026 If your sales cross multiple local tax jurisdictions inside a single state, you’ll break out collections by location on the return.
File the Return and Send the Payment
Nearly every state now requires electronic filing through a secure portal on the revenue department’s website. You log in, open the filing section, enter or upload your figures, review the summary, and confirm. The portal generates a timestamp that serves as your proof of timely filing. Save it.
A small number of states still accept paper returns from businesses below a revenue threshold, but electronic mandates have expanded steadily. Whether you file online or on paper, the filing isn’t complete until the payment clears.
Payment options are usually limited to ACH debit, electronic funds transfer, or credit card (sometimes with a convenience fee). ACH debit is the most common: you authorize the state to pull the exact amount due from your business bank account on the scheduled date. When both the return and the payment are processed, the system generates a confirmation receipt with a unique transaction number. That receipt is your evidence the state accepted both.
File a Return Even When You Owe Nothing
You must file a return for every assigned period, even one with zero taxable sales. Skipping a period because nothing is due doesn’t pause your obligation. It creates a delinquency.
Consequences range from automatic late-filing penalties (some states impose flat minimums of $50 or more even on zero returns) to revocation of the sales tax permit after repeated failures. Reinstating a revoked permit is significantly harder than filing the zero return would have been. If your business is seasonal or dormant, contact the revenue department to change your filing frequency or close the account rather than letting returns go unfiled.
Take the Vendor Discount if Your State Offers One
About half of all states reward on-time filers by letting them keep a small percentage of the tax they collected. These vendor discounts or timely filing discounts typically range from 0.5% to 3% of the tax remitted, with a few states allowing up to 5% on initial amounts collected.2Federation of Tax Administrators. State Sales Tax Rates and Vendor Discounts Most states that offer the discount also cap it, with monthly maximums commonly between $25 and $500.
The discount is applied on the return form itself, reducing what you remit. You forfeit it entirely if the return is even one day late. There is no partial credit.
Accelerated Schedules for High-Volume Collectors
Several states require high-volume businesses to remit more often than monthly, sometimes semi-monthly or weekly. Thresholds vary, but accelerated schedules generally kick in when average monthly liability exceeds somewhere between $10,000 and $50,000.
Accelerated filers are often required to prepay tax for the first portion of a month before the full figures are available, with the estimate typically based on half of the prior month’s liability. The state reviews your history annually and gives written notice (usually 30 to 40 days) before the first accelerated payment is due. If sales decline and average liability stays below the threshold for one to two consecutive years, you can petition to return to the standard cycle.
Penalties, Interest, and Personal Liability
Late-filing penalties vary by state but follow a consistent structure. Most states impose an initial penalty of 5% to 10% of the unpaid tax, with additional charges accruing at 1% to 5% per month until they reach a cap that typically falls between 25% and 50% of the tax due. Some states assess a flat minimum penalty even when the amount owed is small.
Interest runs on top of penalties and is calculated separately. Rates vary but generally work out to somewhere around 6% to 12% annually on unpaid balances. Interest accrues from the original due date and compounds monthly in many jurisdictions. Unlike penalties, interest usually has no cap.
Personal liability is where sales tax delinquency turns dangerous. Because the money is held in trust, most states allow the revenue department to pursue individual officers, directors, or managers personally for unremitted amounts. This liability is not dischargeable in bankruptcy in many cases, and the state treats it much the way the IRS treats unpaid payroll taxes. The business structure will not shield you. Willful failure to remit can also support criminal charges for theft of government funds.
Fixing a Mistake After You’ve Filed
If you find an error on a filed return, file an amended return rather than waiting for the state to notice. Most states let you amend through the same online portal you used originally. Select the period, enter the corrected figures, and submit. Payments from the original return carry over, and any additional tax, penalty, or interest recalculates automatically.
For older periods that aren’t available to amend electronically, submit a paper copy of the original return marked “Amended Return” at the top, with the original entries crossed out and corrected figures written in, and include a cover letter explaining what changed.
If the amendment shows an overpayment, most states treat the amended return itself as the refund claim. No separate form is needed. Refund claims are subject to time limits, typically three to four years from the date the tax was paid, and some states allow less. File the amendment as soon as you find the error.
Keep the Records That Back Up the Return
Filing doesn’t end your obligation to the underlying data. Most states require you to keep filed returns and supporting sales records (invoices, receipts, exemption certificates, resale certificates, and bank statements) for at least three to four years after the return was filed.
Exemption certificates deserve extra care. If a customer gave you a resale certificate and you can’t produce it during an audit, you owe the tax. The certificate is your only defense. Store these separately from general transaction records and keep them easy to retrieve by customer name.
After each remittance, reconcile your bank statement against the confirmation receipt from the state to confirm the correct amount was debited. If something’s off, contact the revenue department right away rather than waiting for the next filing period. Catching errors early keeps penalties and interest from accruing on amounts the state believes you still owe.
Remitting in More Than One State
Since the U.S. Supreme Court’s 2018 decision in South Dakota v. Wayfair, states can require remote sellers to collect and remit sales tax even without a physical presence. The threshold most states have adopted is $100,000 in sales into the state during the current or prior calendar year. About 18 states also maintain an alternative threshold of 200 or more separate transactions, so transaction volume alone can create an obligation even when your dollar amount is lower.
Each state has its own registration, rates, forms, frequencies, and deadlines, and the compliance work multiplies with every state you sell into. The Streamlined Sales and Use Tax Agreement was built to reduce that friction. About two dozen states participate as full members, and the Agreement’s online system lets you register in all participating states through a single free form.3Streamlined Sales Tax. Seller’s Guide to the Streamlined Sales Tax Registration System
One boundary to keep in mind: the Streamlined system handles registration only. You still file and pay each state individually, and the Agreement only covers its member states. If you have economic nexus in a non-member state, you’ll register and file there separately. For businesses selling into more than a handful of states, dedicated sales tax automation software is close to a necessity for keeping the returns accurate and on time.