Yes—but the Maryland Tax Court ruling does not automatically change every seller’s filings. The court ruled the state’s Digital Advertising Gross Revenues Tax unlawful in cases brought by three companies, but the Comptroller appealed, and the decisions do not by themselves resolve every other business’s filing or payment obligations. If your business provides digital advertising services and has Maryland-attributed ad revenue, review your filing position before stopping payments or amending returns.
Key takeaways
- The Tax Court ruled against Maryland’s digital advertising tax in cases involving three taxpayers, but the Comptroller appealed.
- Form 600 generally applies to providers with at least $1 million in Maryland-attributed digital advertising revenue—not simply ecommerce sellers that buy ads.
- Check the current Form 600 and Form 600D instructions for deadlines; the Comptroller’s online fourth-quarter date has differed from the statutory schedule.
- Review payment-by-payment refund deadlines promptly; Form 600 instructions state a three-year period for amended returns from payment.
- Keep advertising-tax analysis separate from sales-tax nexus, marketplace sales, and digital-product taxability.
What the Maryland ruling means right now
The Maryland Tax Court ruled for three taxpayers and held the Digital Advertising Gross Revenues Tax unlawful. It ordered refunds for those taxpayers. The Comptroller appealed the decisions to circuit court, so the dispute is not necessarily over. The ruling is important, but it is not a blanket instruction that every business may stop filing or paying.
For businesses outside those cases, the practical question is how to comply while the appeal proceeds and how to protect potential refund rights. The Comptroller’s current forms and statutory provisions continue to describe filing and payment requirements. Before changing a return, payment, or registration, confirm the current status with the Comptroller or get advice based on your business’s facts.
What the tax covers—and which businesses may be affected
Maryland’s Digital Advertising Gross Revenues Tax is a tax on gross revenues derived from digital advertising services in Maryland. It is not a general tax on every online sale, marketplace transaction, website, or digital product. A seller using online ads to promote products is not automatically a provider of taxable digital advertising services merely because it buys advertising.
The statutory filing threshold is at least $1 million in annual gross revenues derived from digital advertising services in Maryland. The tax’s rate structure also uses a business’s global annual gross revenues. The Maryland Tax Court found that aspects of the tax’s treatment of global revenue and digital advertising raised legal problems. Whether a particular business’s services and receipts fall within the law depends on what it provides, who pays it, and how the revenue is sourced to Maryland.
Keep this issue separate from sales tax. A seller’s sales-tax duties may depend on Economic nexus in Maryland, while the digital advertising tax concerns revenue from providing advertising services. Likewise, state treatment of SaaS and digital products varies: see our articles on SaaS and digital product sales tax in Alabama, Arizona, California, and Illinois for those separate questions.
Who must register and file Maryland Form 600?
Under Maryland law, a person with at least $1 million in annual gross revenues derived from digital advertising services in Maryland must file a digital advertising gross revenues tax return with the Comptroller. The annual return is Form 600. The statutory threshold is based on Maryland-attributed digital advertising revenue, not simply total company sales or the value of products sold through Amazon, Shopify, Etsy, or Walmart.
Businesses that reasonably expect their Maryland digital advertising gross revenues to exceed $1 million for the year also have estimated-tax declaration and payment requirements. The Comptroller’s Form 600 materials direct taxpayers to use Form 600D for estimated payments. Registration and account requirements can depend on the business’s circumstances; confirm them with the Comptroller rather than assuming that a sales-tax registration alone satisfies this tax’s requirements.
If you are unsure whether your business sells advertising services or merely purchases ads, review contracts, invoices, revenue accounts, and the actual service delivered. The exact position depends on your circumstances—confirm with the state, or talk to us and we will check it for you.
Form 600 and estimated-payment deadlines
The annual Form 600 is due by April 15 following the close of the tax year. Maryland’s statute and current Form 600 instructions state that businesses meeting the estimated-tax expectation test must make estimated payments during the year. The statutory schedule calls for the declaration by April 15 and quarterly estimated-tax returns by June 15, September 15, and December 15. The Comptroller’s current online deadline page has listed a different fourth-quarter date, so verify the applicable date and form instructions for the tax year before relying on a calendar reminder.
The Form 600 instructions describe an estimated-payment safe-harbor calculation: total payments generally must reach at least 90% of the current-year tax or 110% of the prior-year tax, with at least 25% of the required total paid by each installment date. These calculations and any penalty or interest exposure depend on the year and the taxpayer’s facts. Do not assume that an appeal suspends a due date.
For other state filing questions, destination sourcing can also change how a seller reports transactions; see our article on Philadelphia’s move to destination sourcing. That is a separate sales-tax issue from Maryland’s digital advertising gross revenues tax.
Should you keep filing or paying during the appeal?
There is no one-size-fits-all answer. The Tax Court’s decisions favor the named taxpayers, but the Comptroller appealed, and other businesses should not assume the decisions automatically excuse their own returns or payments. Continuing to file or pay may preserve compliance while the case is pending, but it can mean paying a tax that may later be refundable. Stopping may create exposure to assessments, interest, or penalties if the state’s position ultimately prevails.
Before a due date, assess whether the business is actually within the tax, the amount at stake, the appeal’s status, and the consequences of each option. Ask the Comptroller or a qualified tax adviser about the current administrative position and whether a protective filing or payment approach is appropriate. Sales Tax Compliance USA can help review sales-tax compliance and records, but a contested tax-law position may require advice from a tax attorney or other qualified adviser.
Refunds: eligibility, lookback, and claim deadlines
The Tax Court ordered refunds for the three taxpayers in the cases before it; that does not automatically issue refunds to every business that paid the tax. Other businesses may need to file their own refund claims and follow the Comptroller’s procedures. Eligibility depends on whether the business paid the tax, whether it was legally liable, the periods involved, and whether a timely claim is available.
The Comptroller’s Form 600 instructions state that amended returns must be filed within three years from the date the tax was paid. That is a key deadline to review, but do not treat it as a universal answer for every claim type or payment. The applicable deadline can depend on the payment, return, assessment, and procedural route. Maryland law also provides a 30-day period to challenge certain tax assessments or, where applicable, submit a refund claim after an assessment notice is mailed.
Build a payment-by-payment schedule now: identify the tax period, payment date, amount, return, and any assessment or prior refund request. Preserve proof of payment and correspondence. If a deadline may be approaching, confirm the correct claim procedure promptly with the Comptroller or counsel; waiting for the appeal to finish could put a claim at risk.
Why the Tax Court found the tax unlawful
The court’s decisions concluded that the tax violated the federal Internet Tax Freedom Act because Maryland taxed digital advertising without imposing a similar tax on non-digital advertising. The court also found constitutional problems under the Dormant Commerce Clause and the Due Process Clause, including concerns about discrimination against interstate commerce and the use of global revenue in determining taxability and rates.
Those are the Tax Court’s conclusions in the cases before it, not a final statewide resolution while the appeal is pending. The appeal may affirm, modify, or reverse the decisions. Businesses should distinguish the court’s legal reasoning from the current practical status of their own accounts and filing obligations.
Review filings, preserve records, and watch other states
Review prior returns, estimated payments, invoices, contracts, customer and advertiser records, revenue classifications, and the method used to attribute advertising revenue to Maryland. Keep copies of filed Forms 600 and 600D, payment confirmations, amended returns, notices, and communications with the Comptroller. These records can help determine whether the tax applied and support a refund claim or response to an assessment.
The Maryland ruling does not automatically invalidate digital advertising taxes in other states. Each state’s statute, tax base, sourcing rules, and constitutional issues must be evaluated separately. It may prompt businesses to review similar obligations, but it does not change sales-tax rules for SaaS or digital products in Alabama, Arizona, California, or Illinois. For sellers operating across states, keep advertising-tax analysis distinct from sales-tax nexus and product-taxability reviews.
Not sure how this applies to your business? We handle US sales tax registration, filing and remittance for ecommerce sellers as a fully managed service, for one fee. Book a free consultation and we will review your own position with you.
Maryland digital advertising tax: practical filing and review points
| Issue | Maryland rule or current status | What a business should check |
|---|---|---|
| Annual return | Form 600 is due April 15 following the tax year for a person meeting the statutory Maryland digital-advertising revenue threshold. | Whether the business provides digital advertising services and how much qualifying revenue is attributable to Maryland. |
| Estimated tax | Form 600D applies when the business reasonably expects Maryland digital advertising revenue to exceed the statutory threshold; installment dates and instructions should be checked for the relevant year. | Current Comptroller instructions, expected tax, prior-year tax, installment amounts, and any payment already made. |
| Tax Court ruling | The Tax Court ruled the tax unlawful in cases involving three taxpayers; the Comptroller appealed. | Whether the appeal or later state guidance changes the position before the next filing or payment date. |
| Refund review | The court ordered refunds for the named taxpayers. Other taxpayers must assess and pursue their own claims. | Payment dates, return periods, claim procedure, and the applicable limitation period; Form 600 instructions state a three-year period for amended returns from payment. |
| Online sellers | Buying online ads or selling through an ecommerce marketplace does not by itself establish that a seller provides taxable digital advertising services. | Contracts, invoices, revenue sources, and whether the business sells advertising services rather than purchasing them. |
Frequently asked questions
What is Maryland’s digital advertising gross revenues tax?
It is a Maryland tax on gross revenues derived from digital advertising services in the state. It is distinct from sales tax on products or marketplace sales. The statute also uses global annual gross revenues in its rate structure.
Who has to file Maryland Form 600 for the digital advertising tax?
A person with at least $1 million in annual gross revenues derived from digital advertising services in Maryland must file the annual return, Form 600. A business that merely buys ads to promote its products is not automatically a provider of those services.
What are the filing and estimated-payment deadlines?
Form 600 is due April 15 following the tax year. The statute provides for an estimated-tax declaration by April 15 and quarterly estimated-tax returns by June 15, September 15, and December 15; check the Comptroller’s current instructions for the applicable tax year because its online deadline page has shown a different fourth-quarter date.
Did the Maryland Tax Court strike down the digital advertising tax?
The Tax Court held the tax unlawful in decisions involving three taxpayers and ordered refunds for them. The Comptroller appealed, so the dispute remains subject to further review and the decisions do not automatically resolve every other business’s obligations.
Should companies keep filing or paying while the ruling is appealed?
The ruling does not provide a universal answer for businesses that were not parties to the cases. Stopping payments may create exposure if the state’s position is upheld, while continued payments may later require refund claims. Review your facts and the current appeal status with the Comptroller or a qualified adviser before changing course.
Can businesses claim refunds for Maryland digital advertising taxes already paid?
Potentially, but the Tax Court’s refund orders applied to the taxpayers in those cases and do not automatically refund other businesses. A business should review its liability, payment history, claim procedure, and deadlines, and file a timely claim if appropriate.
How far back can a business claim a refund?
The Comptroller’s Form 600 instructions say amended returns must be filed within three years from the date the tax was paid. The deadline and procedure can depend on the type of claim and circumstances, so verify the applicable rule for each payment rather than assuming every period remains open.
Does the Maryland ruling affect digital advertising taxes in other states?
Not automatically. The ruling concerns Maryland’s law, and other states’ taxes must be assessed under their own statutes and legal issues. It is a reason to review other obligations, not proof that another state’s tax is invalid.
Official sources
- https://mgaleg.maryland.gov/mgawebsite/Laws/StatuteText?article=gtg§ion=7.5-201
- https://www.marylandcomptroller.gov/content/dam/mdcomp/tax/forms/2025/600.pdf
- https://www.marylandcomptroller.gov/content/dam/mdcomp/tax/forms/2024/600D.pdf
- https://services.marylandcomptroller.gov/taxes/en/filing-deadlines-and-due-dates?id=kb_article_view&sysparm_article=KB0010037
- https://mgaleg.maryland.gov/mgawebsite/laws/StatuteText?article=gtg§ion=13-508
Related reading
- Economic nexus in Maryland
- How does philadelphia’s move to destination sourcing change filings?
- SaaS and digital product sales tax in Alabama
- SaaS and digital product sales tax in Arizona
- Our sales tax compliance services
Getting this handled
If you would rather not work this out yourself, that is what we do. We register you, file your returns and keep you compliant across every state where you have an obligation — one point of contact, one invoice. Talk to us about your situation.
Reviewed by Paul le Roux, CA(SA). Sales Tax Compliance USA handles US sales tax registration, filing and remittance for cross-border and domestic ecommerce sellers as a fully managed service.
This article is general information for educational purposes and does not constitute legal or tax advice. Sales tax rules change and depend on your specific facts. Consult a qualified tax professional about your own position.