Maryland’s 3% tech tax on custom software: one invoice, six answers

What Maryland actually taxes now

Maryland has never taxed services as a category. Its sales and use tax reaches tangible goods, digital products, and a short list of services that the General Assembly has added one at a time over the decades: cleaning a commercial building, guarding one, answering its phones, reporting on its customers’ credit. Until the summer of 2025 that list, in §11–101(m) of the Tax‑General Article, ran to thirteen items. The Budget Reconciliation and Financing Act of 2025, House Bill 352, which became Chapter 604 of 2025 when Governor Moore signed it on 20 May, added two more:

“(14) a data or information technology service described under NAICS Sector 518, 519, or 5415; or (15) a system software or application software publishing service described under NAICS Sector 5132.” — Md. Tax‑General §11–101(m)

It set the rate a few pages later:

“The sales and use tax for a sale of a taxable service described under § 11–101(m)(14) and (15) of this subtitle is 3% of the taxable price.” — Md. Tax‑General §11–104(l)(1)

That is the whole statutory change, and it is worth noticing how little of it is written in Maryland’s own words. The statute never says software, website or cloud. It points at the North American Industry Classification System, a federal manual designed so the Census Bureau can count establishments, and borrows its category descriptions wholesale. Nearly every argument since then about what is and is not taxable has really been an argument about how a document written for statisticians should be read by an auditor. One thing, at least, is simple. Maryland does not let counties or cities add a sales tax of their own, so 3% is 3% in Baltimore City, in Towson and in Ocean City alike.

Your own NAICS code does not decide it

The first thing most people reach for is their own code: the six digits on a federal return or on a government contract. The Comptroller closed that door in the second question of Technical Bulletin 56, the question-and-answer guide it published on 10 June 2025 and revised on 30 June, the day before the tax began:

“The classification that a business reports as their primary business activity code for federal and state income tax purposes is not determinative of whether sales and use tax is imposed on sales of services by the business.” — Comptroller of Maryland, Technical Bulletin No. 56, question 2

Each service is tested on its own. An agency that thinks of itself as a marketing firm still collects the tax on the landing page it builds, because a landing page is custom webpage design. A procurement solicitation that names a NAICS code does not settle anything either; the bulletin says so in the next paragraph. What decides the question is the service itself, held up against a list.

The list, in plain words

The list exists, which is the good news, and it is more specific than most of the commentary about it. The Comptroller published it in the bulletin and in the Code of Maryland Regulations as COMAR 03.06.01.48: ninety-three entries across the four codes. Under subsector 5415 it names, among thirty-two entries, custom computer programming services, custom software programming, custom computer software analysis and design, custom computer software support, computer software consulting, computer software installation and computer disaster recovery — and two that tend to surprise people: custom webpage design services, and custom search engine optimization. Under sector 518 it names web hosting, cloud storage, application hosting, infrastructure and platform as a service, and data entry. Under 519, between the libraries and the archives, it names the provision of stock photos. Under 5132 it names software publishing and packaged software.

Here is how that list lands on what a small Baltimore business actually pays for. I have kept to items the regulation names, and I have marked the two carve-outs it writes into its own text.

Two rows need a sentence each. The percentage your card processor takes from every sale is not taxed under this item, because the regulation defines the data processing entry as data processing “except payroll services, financial transaction processing services”; the carve-out sits inside the definition itself. And the subscription row says 3% only because the buyer is a business. That is the next rule, and it is the one that most often surprises people who think they already understand the tax.

When two rates could apply, the higher one wins

“If a different rate from the rate specified under paragraph (1) of this subsection could be applied to a sale or use of tangible personal property, a digital code, a digital product, or a taxable service, the higher rate shall apply to the sale.” — Md. Tax‑General §11–104(l)(2)

Software as a service is two things at once under Maryland law. It is a digital product, taxable at 6% since 2021, and since July 2025 it is also a software publishing service, taxable at 3%. The Comptroller untangles the two through the definition of a digital product, which excludes software bought solely for use in an enterprise computer system. Bought by a business for its own systems, SaaS falls outside that definition and is taxed only as a service. Bought by a person for personal use, it stays a digital product, and the higher rate wins:

“This means that SaaS sold for individual use is taxed at the 6% rate, and the same SaaS is taxed at the 3% rate when sold for use in an enterprise computer system.” — Technical Bulletin No. 56, question 6

So the rate on a subscription is not a property of the software. It depends on who is buying it and what for: a project-management tool bought by a company for its staff is a 3% purchase, and the identical tool bought by an individual for personal use is a 6% one. The same bulletin closes a door that used to be open. Maryland once exempted, from its tax on digital products, software that had to be customized, configured or modified before it worked for the buyer; question 7 says that exemption was repealed on 1 July 2025. Custom used to be a way out. It is now written into the list by name.

The market that got taxed

Before the arithmetic, a word about who sits on the other side of these invoices, because it explains a lot about how the tax has behaved in its first year. I pulled the Census Bureau’s County Business Patterns for 2023, the most recent year published, for the industries the statute names. Two method notes. CBP counts only establishments with paid employees, so the freelance developer working alone is not in it. And CBP 2023 still files software publishers under the 2017 code, 511210, whereas the tax cites the 2022 code, 5132, for the same activity; I have left out sector 519, whose 2017 and 2022 definitions differ too much to line up honestly.

Three things stand out. The first is size. Two out of every three of these establishments have fewer than five employees — 3,918 of the 5,945 — which means the typical business that had to start collecting Maryland’s newest tax is a shop about the size of ours, not a federal integrator near Fort Meade. The second is geography. Baltimore City holds 8.66% of all Maryland establishments with employees but only 3.94% of the state’s computer services establishments: 206 of the 5,227 in subsector 5415. Howard County alone has 1,002, which is 4.86 times the city’s count. The third is money: $13.2 billion of annual payroll across the six industries, and an average of $115,750 per employee in the four computer-services codes statewide, against $103,534 in the city.

None of that tells you who pays. The tax falls on the use of these services in Maryland, not on Maryland’s technology industry. A Howard County firm building software for a client in Virginia charges no Maryland tax at all, while a Baltimore bakery that buys a website from a firm in California owes 3% whether or not the California firm collects it. The industry in that table is the one that had to learn to collect. The people who pay are its Maryland customers, which is to say nearly every business in the state.

The estimate and the money

When the General Assembly passed the tax, the Department of Legislative Services estimated it would raise $482.8 million in fiscal 2026 and $747.4 million by fiscal 2030. The fiscal note was candid about its own limits. It was built from 2012 Economic Census data scaled to Maryland’s 2026 economy, it left out sole proprietors and sellers outside the state, and it had already trimmed the first year to allow for a slow start:

“The fiscal 2026 estimate discounts expected revenues by 25% to account for start-up and initial compliance issues.” — Department of Legislative Services, Fiscal and Policy Note on HB 352, 2025 session

The first year produced $112.8 million, paid by about 2,900 companies, according to Comptroller’s Office figures reported on 1 September 2026 (GovTech). That is 23.36% of the estimate, or $370.0 million short. The Comptroller’s explanation, in substance, is that the original number was made before real data existed and that its projections now rest on actual collections.

It is worth being careful with a gap that size, because it is tempting to read it as proof of something. The fiscal note had already listed the reasons taxable sales might shrink: buyers deciding not to buy, purchases moving to a neighboring state, and sales to governments and nonprofits, which are exempt. It added one more, which matters for everything that follows:

“To the extent that businesses decrease their purchases of these services, by performing the services in-house, for example, revenues are lower.” — Fiscal and Policy Note on HB 352, 2025 session

There is one comparison I can make from public data, and I will make it only once. About 2,900 companies paid the tax. Maryland alone has 5,945 establishments with employees in the industries it names, before counting a single cloud or software vendor based anywhere else. An establishment is a location, not a company; many of those shops sell mainly to the federal government, which does not pay Maryland sales tax; some sell only to clients in other states. So 2.05 establishments for every paying company is not a compliance rate, and I would not quote it as one. What it does show is a population of sellers that is enormous and mostly small, and that is the practical reason the buyer-side rules below matter as much as they do.

The state, meanwhile, is still budgeting on the higher line. The December 2025 revenue forecast, which the 2026 fiscal notes rely on, assumes $609.0 million from this tax in fiscal 2027 and $769.9 million in fiscal 2031 — 5.40 times what the first year produced. Some of that difference is genuine start-up. Some of it will turn out to be optimism. For a buyer the reading is simple enough: a state counting on six hundred million dollars from a tax is not going to drop it quietly.

Being fair to the tax

I have spent much of this series pointing at rules that were drafted badly for the businesses they land on. This is not really one of them, and it would be dishonest to write about it as if it were.

The rate is low: half the general Maryland rate, on services that could have been added to the 6% list. The base is broad, which is what economists usually ask of a tax. The same 3% falls on a cloud bill from Seattle and a custom build from Hampden, so the tax does not tilt a buyer toward either. And the guidance is genuinely good. Technical Bulletin 56 answers the timing questions most states leave to an audit, works through subscriptions, milestone contracts and change orders, and even suggests two acceptable ways to split a multi-state license, by employees or by seats. As tax guidance goes it was early, clear and specific, and I have leaned on it for most of the rules in this post.

The honest objection is structural. A 3% tax on business-to-business services is largely a tax on inputs: the business buying the software is usually not the end consumer of anything, so the cost reappears in the price of whatever that business sells. Senate Bill 600 tried to address that in 2026 by excluding services bought to be built into other taxable services, along with sales between related companies. The Comptroller estimated that 37.5% of these industries’ output is consumed as exactly that kind of input, and the fiscal note priced the change at $228.4 million in fiscal 2027. It never came out of committee. The narrower fix that did pass costs about a sixth of that, and it is one of the six answers below.

One invoice, six answers

Here is the part no rate card shows. Take one invoice: a $12,000 custom application, the starting price of our Custom App package, built for a business in Baltimore. Change nothing about the software. Change only the facts around it, one at a time, and watch what Maryland collects and who has to hand it over.

Three of those six answers are zero, one is a number nobody would guess, and in two of them it is the buyer, not the vendor, who has to send the tax to the state. None of it depends on the code. Here is each one in turn.

The date on the contract, not the date on the check

Maryland decides when a sale happens by looking at the kind of contract, and the difference between a subscription and a project turns out to be the most practical distinction in the whole tax. A build like ours is what the bulletin calls an installment sale: one agreed total, paid in pieces, often on milestones. For those, the sale happens when the parties agree on terms and sign. That is why a project signed in June 2025 and paid in stages through the fall owed nothing:

“No sales and use tax is due on this transaction because the parties agreed on terms and executed the contract before July 1, 2025.” — Technical Bulletin No. 56, question 14

The protection runs exactly as far as the original contract and not a line further. An option written into that contract and exercised later is still part of it, so it stays untaxed. A change order that adds work the contract did not describe is not:

“The change order for additional services not described in the original contract is considered a new sale, even though it is effectuated by a change order to a contract entered into before July 1, 2025.” — Technical Bulletin No. 56, question 16

A subscription is a new sale every month

Subscriptions work the other way. The bulletin treats each payment as its own sale, so a monthly plan that began in 2024 became taxable with its first payment after 1 July 2025, and an annual contract that renewed itself became taxable on renewal:

“Each subscription payment is considered a separate sale for the purpose of determining when the tax is imposed.” — Technical Bulletin No. 56, question 11

Put the two rules side by side and a useful asymmetry appears. The tax on a build is fixed on the day you sign it. The tax on a subscription follows the law payment by payment: if the rate rises, the next invoice rises with it, and if the tax is repealed, the first payment after the repeal takes effect drops it. Whether that argues for signing a build before or after some future change depends entirely on transition rules nobody has written yet, and I would not move a contract by a single day on the strength of a bill that does not exist. But it is worth knowing which of your costs is locked and which one floats.

The certificate that moves the tax to you

Row three is the multiple-points-of-use certificate, usually shortened to MPU, and it is the part of this tax that asks the most of the buyer. Under §11–403(e), a buyer who knows at the time of purchase that a digital product or a taxable data, IT or software service will be available for use both inside and outside Maryland at the same time can hand the vendor a certificate instead of paying the tax. The vendor stops collecting. The buyer works out the Maryland share and pays use tax on it directly, using

“any reasonable but consistent and uniform method of apportionment that is supported by the buyer’s records as they exist at the time of the sale and accurately reflects the primary use location in the State.” — Md. Tax‑General §11–403(e)(3)

The bulletin offers two such methods: the share of the employees using the service who are in Maryland, or the share of the licenses. In our example 9 of the buyer’s 14 users work in Maryland, so 64.29% of the $12,000 is Maryland use and the tax is $231.43 instead of $360.00. There is no minimum or maximum share, but the vendor must refuse a certificate if it knows or should know that the service will be used entirely in Maryland. To issue one at all, the buyer needs its own sales and use tax account and authorization from the Comptroller. The Comptroller’s Office reported that 751 certificates had been issued through January 2026.

Is it worth it? On a single $12,000 build the certificate saves $128.57 and costs a registration, an authorization, the certificate itself and a use-tax return. For a Baltimore business with a couple of people working from Pennsylvania, I would pay the $360 and move on. For a company whose software spending runs to tens of thousands of dollars a year across several states the answer is different, and it changes again on 1 January 2027. Under Chapters 197 and 198 of 2026, Senate Bill 644 and House Bill 933, the authorization will renew every two years; the buyer will give each vendor one certificate, which stays in effect for future purchases until it is rescinded or the authorization is revoked; and the buyer must tell the vendor, and pay the tax, on any purchase it expects to be used only in Maryland. That is far less paperwork than the per-transaction system it replaces. The Comptroller’s Office warned that it could also make certificates harder to verify, and the fiscal note budgets $183,400 in fiscal 2027 for two more auditors to check them. One more date sits alongside it: for periods beginning after 31 December 2026, sales and use tax returns must be filed electronically, so a business that registers in order to use certificates will be filing online.

Sister companies, since this July

Row four is the exemption the 2026 session added. When the tax started, the Comptroller was explicit that an internal services company billing its sister companies owed the tax like anyone else, and that doing the work at cost made no difference:

“There is no exemption for sales made to affiliated company members.” — Technical Bulletin No. 56, question 4

From 1 July 2026 there is. Section 3 of Chapters 351 and 352 of 2026, the DECADE Act (Senate Bill 388 and House Bill 898), exempts sales of data and IT services, software publishing services, digital codes and digital products when the vendor and the buyer belong to the same affiliated group. The definition is borrowed from federal law: an affiliated group under §1504 of the Internal Revenue Code, plus the related parties described in §267(b)(10), (11) and (12), which reach certain pairs of corporations, S corporations and partnerships under common ownership. The Department of Legislative Services put the cost at $35.5 million in fiscal 2027 and $47.3 million in fiscal 2028, on the Comptroller’s estimate that it removes about a tenth of the revenue from these services and digital goods. If one of your companies pays for software another one uses, or buys its IT from a sister company, ask your accountant whether your entities fit that definition. It is a better question than it sounds.

Nonprofits

Row five is the exemption that was always there. Charitable, religious and educational organizations that hold a Maryland sales and use tax exemption certificate — the wallet-sized card the Comptroller issues, known as a SUTEC — pay no tax on purchases made to carry out their purpose, and the bulletin confirms that includes these services. The vendor records the certificate number and keeps it for at least four years. If you run a Baltimore nonprofit, we wrote about the rest of your software stack in a separate post.

The vendor who never registers

Row six is the one I would most want a small business to understand. An out-of-state seller has to register and collect Maryland tax once it passes $100,000 of gross revenue from sales delivered into the state, or 200 separate transactions, in the current or previous calendar year (COMAR 03.06.01.33). Below that line, a small software vendor or a freelance developer in another state may never charge you a cent of Maryland tax. That does not mean nobody owes it. Maryland taxes the use as well as the sale:

“(a) Except as otherwise provided in this title, a tax is imposed on: (1) a retail sale in the State; and (2) a use, in the State, of tangible personal property, a digital code, a digital product, or a taxable service.” — Md. Tax‑General §11–102(a)

So a quote from out of state that leaves the tax line off is not 3% cheaper. It moves the line from the vendor’s invoice to your books, where it becomes use tax you are expected to report yourself. Nor can a contract make the tax disappear. A contract that says the price includes all taxes, or forbids the vendor from charging any, changes who bears the cost but not whether it is owed; the bulletin says a registered vendor in that position must absorb the tax and remit it anyway:

“A contractual agreement between the buyer and the seller does not change the taxability of the transaction.” — Technical Bulletin No. 56, question 26

The one version of this work the tax cannot see

There is one way to get software built in Maryland that this tax never sees, and the fiscal note named it: do it in-house. A salary is not a sale. The developer on your payroll can build the same $12,000 application and Maryland collects nothing on the work.

Before you let that push you toward hiring, run the arithmetic the other way. An employer pays Social Security and Medicare tax of 7.65% on wages — 6.2% up to the Social Security wage base and 1.45% on all of it — before benefits, equipment, recruiting, or the months it takes anyone new to become productive. On $100,000 of development work, hiring avoids $3,000 of sales tax and takes on $7,650 of payroll tax. That does not make hiring wrong; plenty of businesses should have a developer on staff. It means the 3% is a reason to read your invoices carefully, not a reason to change how you build.

The e-commerce half: what an online store pays, and what it collects

A good share of the work we do for Maryland businesses is online stores, most of them selling physical things: food, clothing, prints, parts. For a store this tax shows up twice, on opposite sides of the ledger and at different rates, and it helps to see both at once.

The asymmetry is the useful part. The store pays 3% on its machinery and collects 6% on what passes through it, and the two never meet. Maryland’s sales tax gives no credit for tax paid on your own business purchases, so the 3% on your build or your platform is a cost, not an offset against the 6% you remit. What does interact with the tax is the platform decision. On a subscription platform the 3% recurs every month for as long as the store exists; on a store you own, the build’s 3% is paid once, and what recurs is hosting, which is on the list too but is usually a small number.

In round numbers: a $300-a-month stack of store platform and apps carries $9.00 of tax a month, $108.00 a year and $324.00 over three years. Our Online Store starts at $6,000 and carries $180.00, once. Neither figure is big, and neither should decide anything on its own. For the rest of that comparison, we walked through a whole store build, Friday to Sunday, and wrote a plain decision guide to custom versus SaaS versus no-code. If your store keeps customer data, Maryland’s privacy law has a threshold of its own, which we worked through in Maryland’s Online Data Privacy Act for online stores.

What the 3% adds to our fixed prices

We publish four fixed prices and we do not move them from client to client. A Maryland business using the software in Maryland pays the 3% on top of each one, as it would with any other studio, and here is exactly what that looks like.

Three details matter more than the totals. The tax is calculated on the price agreed when you sign, so it does not drift during the build. Anything added later by change order is a new sale with its own 3%, which is one more reason we fix the scope before anyone writes code; we explained the rest of that reasoning in why we fixed-price everything. And the accounts we set up are in your name — hosting, domain, payment processor — so those bills come to you directly, with their own tax lines where the provider charges them.

What I would check on your next software invoice

If you run a Maryland business, this is the whole practical checklist, and it is the only list in this article.

• Look for the line. An invoice from a registered vendor for anything on the list should show 3%, or 6% if the subscription is for personal use. If a subscription shows no tax at all, find out whether the vendor is registered in Maryland; if it is not, the tax is yours to report as use tax.
• Check the dates on old contracts. A milestone contract signed before 1 July 2025 sits outside the tax even while the payments continue, but every change order since then is a new, taxable sale. Keep the signed original somewhere you can find it.
• Count where your users are. If a real share of a tool’s users work outside Maryland, a multiple-points-of-use certificate can cut the tax to your Maryland share, with a registration and a return attached and new, simpler rules from 1 January 2027.
• Ask about your corporate structure. If one of your companies pays for software another one uses, or buys IT services from a sister company, the affiliated-group exemption that began on 1 July 2026 may apply. Your accountant can tell you whether your entities fit the federal definition.
• Don’t let 3% make a decision it can’t carry. It falls on SaaS and custom builds alike, and hiring to avoid it costs more in payroll tax than it saves. Decide build or buy on everything else.

Who we are

We are a small studio in Baltimore that builds custom software at a fixed price. You work directly with the people who write the code, and you own everything when we finish. We have written this blog one Baltimore trade at a time — driving schools, fitness studios, accounting firms, alarm companies and more than forty others — and nearly every one of those posts ended up with a paragraph about this tax, because it lands on all of them. This is the post those paragraphs were pointing at. If you are still deciding whether custom software makes sense at all, start with our guide to custom software development in Baltimore.

I look after operations and business logic at the studio, which in practice means I am the person who reads the Comptroller’s bulletins so that our quotes are right the first time. If you would like us to look at your stack with you, the call is free, and we will tell you honestly if the answer is to keep what you have.

Common questions about Maryland’s tech tax

Is custom software development taxable in Maryland?

Yes. Since 1 July 2025 Maryland has taxed data and information technology services described in NAICS sectors 518 and 519 and subsector 5415, and software publishing described in subsector 5132, at 3%, under Tax‑General §11–101(m)(14) and (15) and §11–104(l). The Comptroller’s list in COMAR 03.06.01.48 names custom computer programming services, custom software programming and custom computer program or software development expressly. A Maryland business buying a $12,000 custom application for use in Maryland pays $360 in tax. The old exemption for customized software was repealed on the same date.

Is SaaS taxed at 3% or 6% in Maryland?

It depends on the buyer. Under Technical Bulletin 56, software as a service sold for use for commercial purposes in an enterprise computer system is taxed as a software publishing service at 3%. The same SaaS sold for individual use is a digital product, and because §11–104(l)(2) applies the higher rate when two rates could apply, it is taxed at 6%. Each subscription payment is a separate sale, so a subscription that began before 1 July 2025 became taxable with its first payment after that date.

Does Maryland’s 3% tax apply to website design, hosting and SEO?

Yes, all three. COMAR 03.06.01.48 lists custom webpage design services and custom search engine optimization, except hosting and infrastructure support services, under subsector 5415, and web hosting, cloud storage, application hosting, infrastructure as a service and platform as a service under sector 518. It also lists the provision of stock photos under sector 519. Card processing fees are not on the list, because the regulation defines the data processing entry as excluding payroll services and financial transaction processing services.

Is Maryland repealing the tech tax?

Not so far. In the 2026 session House Bill 133, which would have repealed it along with broad rate cuts, and Senate Bill 600, which would have excluded services bought as inputs to other taxable services and sales between related companies, both stalled in committee, and the Senate rejected a repeal attempt during its March budget debate. Two narrower changes passed: Chapters 351 and 352 of 2026 exempt sales between members of the same affiliated group from 1 July 2026, and Chapters 197 and 198 of 2026 rewrite the multiple-points-of-use certificate from 1 January 2027. The tax raised $112.8 million in fiscal 2026 against an estimate of $482.8 million, and calls for repeal in the 2027 session have already begun.

Do I owe Maryland’s tech tax if my software vendor is out of state?

Yes, if you use the service in Maryland. Tax‑General §11–102(a)(2) imposes the tax on a use in the State of a taxable service, so the obligation exists whether or not the vendor collects it. Under COMAR 03.06.01.33 an out-of-state vendor must register and collect once it passes $100,000 of gross revenue from sales delivered into Maryland, or 200 separate transactions, in the current or previous calendar year. Below those thresholds a vendor may never charge you, and the 3% becomes use tax you report yourself.

What is a multiple-points-of-use certificate in Maryland?

It is a certificate a buyer gives a vendor when a digital product or a taxable data, IT or software publishing service will be available for use both inside and outside Maryland at the same time. The vendor stops collecting, and the buyer pays use tax on the Maryland share, apportioned by a reasonable, consistent method such as the share of employees or licenses in Maryland. The buyer needs a sales and use tax account and authorization from the Comptroller, which had issued 751 certificates through January 2026. From 1 January 2027, under Chapters 197 and 198 of 2026, authorization renews every two years and one certificate per vendor stays in effect for future purchases until it is rescinded or the authorization is revoked.

Are sales between related companies exempt from Maryland’s tech tax?

From 1 July 2026, yes, if the vendor and the buyer are members of the same affiliated group. Section 3 of Chapters 351 and 352 of 2026, the DECADE Act, exempts sales of data and IT services, software publishing services, digital codes and digital products between members of an affiliated group as defined in §1504 of the Internal Revenue Code, including related parties described in §267(b)(10), (11) or (12). Before that date Technical Bulletin 56 said there was no exemption for sales to affiliated companies, even at cost. The Department of Legislative Services estimated the exemption would reduce general fund revenue by $35.5 million in fiscal 2027.

How much does Maryland’s tech tax add to a custom software project?

Three percent of the taxable price, fixed when the contract is made. On our published packages that is $105 on a $3,500 Prototype Sprint, $180 on a $6,000 Online Store and $360 on a $12,000 Custom App or Operations System. A contract signed before 1 July 2025 is not taxed even if it is paid later, but a change order after that date that adds new services is a new, taxable sale. A buyer whose users are partly outside Maryland can reduce the tax to the Maryland share with a multiple-points-of-use certificate, and a qualifying nonprofit with a sales and use tax exemption certificate pays none.