# How to File Maryland Sales Tax Online in 2026

Canonical: https://trykintsugi.com/blog/how-to-file-maryland-sales-tax-online
Published: 2026-09-25

How to file Maryland sales tax on Maryland Tax Connect: due dates on the 20th, filing frequencies, the timely discount, no-tax-due returns, and penalties.

Maryland sales and use tax is filed online through **Maryland Tax Connect**, the Comptroller of Maryland's free electronic filing portal, on the **Sales and Use Tax Return**. Returns are due on the 20th day of the month following the end of the period, whether you file monthly, quarterly, semiannually, or annually. Taxpayers making payments of $10,000 or more must file and pay electronically.

This guide covers who files and how often, how to file in Maryland Tax Connect, how to file when you have no tax due, how to amend a return, how to pay, the timely filing discount, and what late filing costs.

This article is educational information, not tax advice. Filing rules, thresholds, and penalties can change, so confirm current requirements with the [Comptroller of Maryland](https://www.marylandtaxes.gov/business/sales-use/index.php) before you file.

## Maryland sales tax filing at a glance

- **Who administers it:** Comptroller of Maryland.
- **Online portal:** Maryland Tax Connect. Online filing and payment are free.
- **Return:** Sales and Use Tax Return.
- **Filing frequency:** Monthly, quarterly, semiannual, or annual, assigned by the Comptroller. New registrants start on quarterly returns.
- **Due date:** The 20th day of the month following the end of the period. A due date on a Saturday, Sunday, or legal holiday moves to the next business day.
- **No tax due:** You can still file electronically in Maryland Tax Connect.
- **Payment:** Free electronic payment, credit card online, or check or money order. Payments of $10,000 or more must be made electronically.
- **Timely filing discount:** 1.2% of the first $6,000 of tax and 0.9% of the amount above $6,000, up to $500 per return.
- **Economic nexus:** Gross revenue from Maryland deliveries over $100,000, or 200 or more separate transactions delivered into Maryland.

## Who has to file, and how often

Every vendor registered with the Comptroller files a sales and use tax return for each assigned period. That includes remote sellers. The Comptroller's guidance says an out-of-state vendor must register if, in the previous or current calendar year, its gross revenue from taxable property or services delivered in Maryland exceeds $100,000, or it made 200 or more separate transactions for delivery into Maryland. Marketplace facilitator sales count toward the threshold, and so do non-taxable and exempt sales. Our [Maryland sales tax guide](/sales-tax-guides/usa/maryland) covers registration and nexus in more detail. Selling digital goods? Our post on [Maryland digital products sales tax](/blog/maryland-digital-products-sales-tax) explains how they are treated there.

The regulation makes monthly filing the default. When a taxpayer is expected to remit less than $100 per month in tax, the Comptroller may assign a less frequent basis. Your first returns are due quarterly, and the Comptroller notifies you in advance of any change in frequency.

| Frequency | How it is assigned | Due date |
| --- | --- | --- |
| Monthly | The default under the regulation | The 20th of the month after the month ends |
| Quarterly | Where new registrants start | The 20th of the month after the quarter ends |
| Semiannual | Assigned when tax is expected to be under $100 per month | The 20th of the month after the period ends |
| Annual | Assigned when tax is expected to be under $100 per month | The 20th of the month after the period ends |

Filers assigned to a schedule less frequent than quarterly must also file a supplemental return for any month in which the tax due for that month exceeds $100.

## Before you start: get into Maryland Tax Connect

You need to be registered with the Comptroller before you can file. Registration gives you a central registration (CR) number, which you use on returns and payments. Our [sales tax permit](/blog/sales-tax-permit) overview explains how registration works. Before filing, gather your records for the period: gross sales, taxable sales, and any deductions. For wholesale sales, see our [Maryland resale certificate](/resale-certificates/maryland) guide for what to collect from buyers.

## Step-by-step: filing a Maryland return

The Comptroller publishes the flow in its bFile help pages for the Sales and Use Tax Return. In short:

1. **Open the Sales and Use Tax Return** in Maryland Tax Connect.
2. **Select the period ending date.** The due date is calculated from it. A quarterly return is not accepted before the first day of the last month of the quarter.
3. **Enter your sales and tax.** Report the amounts for the period.
4. **Review the timely filing discount.** The discount is applied only if you file and pay in full by the due date.
5. **Choose the payment date.** It defaults to the due date, and you can schedule it earlier but not before today. You authorize the withdrawal from your bank account.
6. **Submit and keep your confirmation number.** You need it if you have to modify the return before processing.

Filing in Maryland plus other states? Kintsugi files and remits for you, from $75 per filing, with free monitoring. [Book a demo](/kintsugi-demo) or [start free](https://auth.trykintsugi.com/en/signup).

## Period and discount pitfalls

Most Maryland filing errors come from the period and the discount rather than the amount. Pick the right period ending date, because it cannot be changed after you enter it. A wrong period means deleting the return and filing again. The discount is lost if either the return or the payment is late. Our [Maryland sales tax calculator](/us-sales-tax-calculator/maryland) can help you check the tax you expect on a sale before you report it. Exemptions are a common source of adjustments too, and our post on [Maryland sales tax exemptions](/blog/maryland-sales-tax-exemption) walks through them.

## Due dates and the weekend rule

Maryland uses one day of the month for every frequency: the 20th of the month after the period ends. A September monthly return and a third-quarter return are both due October 20. If the 20th falls on a Saturday, Sunday, or legal holiday, the return is due the next business day. Our [Maryland sales tax due dates](/sales-tax-due-dates#maryland) page lists upcoming dates for every state.

## Filing when you have no tax due

The Comptroller's guidance says that if you have no tax due for the filing period, you can file your sales and use tax and other business tax returns electronically using Maryland Tax Connect. The Comptroller's published guidance does not say whether a return is mandatory when you had no sales, so confirm with the Comptroller if you are unsure about an assigned period.

## Amending a return

The bFile help says you can modify a return you have submitted using its confirmation number, as long as it has not yet been selected for processing. The period ending date cannot be changed, so a return filed for the wrong period must be deleted and filed again. To change a return that has already been processed, the Comptroller directs you to its help page or to 410-260-7980 in Central Maryland or 1-800-638-2937 from elsewhere.

## Payment methods

- **Electronic payment:** Free through Maryland Tax Connect. Taxpayers making payments of $10,000 or more must file and pay electronically.
- **Credit card:** You can pay by credit card online.
- **Check or money order:** Payable to Comptroller of Maryland - SUT, with your CR number on it and any stubs removed, mailed with the return to the Comptroller of Maryland, Revenue Administration Division, 110 Carroll Street, Annapolis, MD 21411-0001.

## The timely filing discount

If you file and pay on time, Maryland lets you keep part of the tax you collected. The discount is 1.2% of the first $6,000 and 0.9% of the amount above $6,000. It may not exceed $500 per return, and a vendor that files or is eligible to file a consolidated return gets a maximum of $500 across all returns. The discount cannot be taken if the return and payment are submitted after the due date.

## Penalties and interest for late filing

A late return carries a penalty of 10% of the tax due, plus interest, which accrues monthly on unpaid amounts. A return or payment that arrives after the due date also forfeits the timely filing discount. The published bFile help does not state the interest rate, so check the Comptroller's current guidance for it.

## Common mistakes to avoid

- **Paying after the due date.** A late payment costs the discount as well as the penalty.
- **Choosing the wrong period ending date.** It cannot be edited, so the return has to be deleted and refiled.
- **Ignoring the supplemental return rule.** Semiannual and annual filers must file for any month where tax due exceeds $100.
- **Mailing a check when the payment is $10,000 or more.** Those payments must be electronic.
- **Counting only taxable sales toward nexus.** Non-taxable and exempt sales count toward the $100,000 and 200-transaction thresholds.

## More state filing guides

Filing in more than one state? These step-by-step guides cover the portals, due dates, and penalties in other states. See them all in our [state-by-state guide to filing sales tax online](/blog/how-to-file-sales-tax-online-by-state).

- [How to file Virginia sales tax online](/blog/how-to-file-virginia-sales-tax-online)
- [How to file Pennsylvania sales tax online](/blog/how-to-file-pennsylvania-sales-tax-online)
- [How to file New Jersey sales tax online](/blog/how-to-file-new-jersey-sales-tax-online)

## Let Kintsugi file for you

If you sell in Maryland and other states, [Kintsugi's sales tax filing software](/product/sales-tax-filing-software) prepares and files returns on each state's assigned schedule and remits payment. Monitoring across every US state is free, so you know when you cross a threshold. Filing starts at $75 per filing or registration, with no per-state subscription. See [pricing](/pricing), [start free](https://auth.trykintsugi.com/en/signup), or [book a demo](/kintsugi-demo).

## Frequently asked questions

### Can I file Maryland sales tax online for free?

Yes. The Comptroller says you can file your sales and use tax return online for free using Maryland Tax Connect, and you can pay electronically for free.

### What form do I use to file Maryland sales tax?

The Sales and Use Tax Return, filed electronically in Maryland Tax Connect.

### When is Maryland sales tax due?

On the 20th day of the month following the end of your period, whether you file monthly, quarterly, semiannually, or annually. If the 20th falls on a weekend or legal holiday, it is due the next business day.

### What is the economic nexus threshold in Maryland?

Out-of-state vendors must register if their gross revenue from taxable sales delivered in Maryland exceeds $100,000, or they make 200 or more separate transactions for delivery into Maryland, in the previous or current calendar year.

### How much is the Maryland timely filing discount?

1.2% of the first $6,000 of tax and 0.9% of the amount above $6,000, up to $500 per return. You lose it if the return or payment is late.

### What if I miss the deadline?

File and pay as soon as possible. A penalty of 10% of the tax due applies, plus interest, and you forfeit the timely filing discount.

## Sources

Checked September 29, 2026.

- Comptroller of Maryland, [Business tax tip #22: Maryland sales and use tax frequently asked questions](https://www.marylandcomptroller.gov/content/dam/mdcomp/tax/legal-publications/tips/business/bustip22.pdf)
- Comptroller of Maryland, [Sales and Use Tax Application Help (bFile)](https://interactive.marylandtaxes.gov/Business/bFile/Help/SalesAndUse_Help_202.aspx)
- Comptroller of Maryland, [Sales and Use Tax filing general information (bFile help)](https://interactive.marylandtaxes.gov/Business/bFile/Help/FSUT_GenInfo_f.aspx)
- Library of Maryland Regulations, [COMAR 03.06.03.03 Returns](https://regs.maryland.gov/us/md/exec/comar/03.06.03.03)
- Comptroller of Maryland, [Sales and use tax alert on remote seller nexus](https://www.marylandcomptroller.gov/legal-library/sut-ta-sep-25-2019.html)