Window Replacement in Maryland: MHIC Licenses and Contracts

In Maryland, the company that signs a window replacement contract with a homeowner has to hold a Maryland Home Improvement Commission (MHIC) license. The Commission licenses and regulates home improvement contractors and salespersons, states that only contractors holding an MHIC license may enter into contracts with homeowners to perform home improvement work, and lists windows, storm windows and window tinting among the types of work that usually require an MHIC license (MHIC; what counts as home improvement; MHIC license search) ¹²³.

On climate, almost all of Maryland, from Baltimore and the Washington suburbs to the Eastern Shore, sits in ENERGY STAR's North-Central zone; only Allegany and Garrett counties in the western mountains are in the Northern zone ⁵⁶.

The MHIC license rule

The Commission's own page sets out the scope (MHIC) ¹:

• What counts. Home improvement work includes alteration, remodeling, repair or replacement of a building or part of a building used as a residence, and work on individual condominium units ¹. Windows are on the Commission's list of work that usually requires an MHIC license ².
• What does not. Work on commonly owned areas of condominiums, and on buildings that contain four or more single-family units, is outside the definition ¹. The Commission's FAQ adds that interior window treatments such as curtains and blinds are decorating, not home improvement ⁸.
• Subcontractors. Maryland eliminated the subcontractor license category as of July 1, 2016. A subcontractor may work without a license when performing home improvements for an MHIC licensed contractor, but only licensed contractors may contract with the homeowner ¹.
• Salespersons. The Commission licenses salespersons as well as contractors, and its search covers both ¹³.

The practical point: the business named on your contract is the one whose license to look up, even if a crew from another company does the installation (MHIC) ¹.

How to check an MHIC license

The Home Improvement Public Query searches active licensees by contractor personal name, trade name, city or ZIP code, salesperson name, or license number ³. The page notes that information about disciplinary actions is available by contacting the Commission ³.

Is the installer licensed by MHIC? Before you sign, check:

• that the license number on the contract matches the business in the search ³⁴;
• that the salesperson who sold the job appears in the search too, if a salesperson was involved ³⁴;
• that the trade name on the quote is the same one the Commission has on file.

The guide on how to choose a window installer covers references, warranties and the rest of the vetting.

What a Maryland window contract must show

The Commission's contracts page sets requirements for the form and content of every home improvement contract, including these (Maryland home improvement contracts) ⁴:

• It is in writing, legible, describes each document it incorporates, and is signed by each party ⁴.
• It describes the home improvement to be performed and the materials to be used ⁴.
• It shows the contractor's name, address and MHIC license number, plus the name and license number of each salesperson who solicited or sold the job ⁴.
• It carries a notice with the Commission's telephone number and website, stating that each contractor must hold a current MHIC license and that anyone can ask MHIC about a contractor ⁴.
• It gives the approximate dates when work will begin and when it will be substantially completed ⁴.
• The homeowner receives a signed copy before work starts ⁴.

The same page sets the deposit rule: a contractor cannot accept more than 1/3 of the contract price as a deposit, and may not accept any payment until the contract is signed. Beyond the deposit, the payment schedule is for the two sides to negotiate ⁴. If the contract includes a mandatory arbitration clause, the page says it must, among other things, name the person or organization that will conduct the arbitration and state whether any mandatory fees will be charged, and the parties must initial and date the contract next to the clause ⁴.

Sales made at your home

The contracts page also says a contract may be covered by the Maryland Door-to-Door Sales Act. When it is, the contract must include a notice that the buyer may cancel before midnight of the fifth business day after the transaction, or midnight of the seventh day if the buyer is at least 65 years old, with a separate Notice of Cancellation form attached (Maryland home improvement contracts) ⁴. If a salesperson wrote your quote in your home, ask whether the Act applies.

The article on how to compare window quotes gives a line-item template that fits alongside this list.

Maryland climate zones for windows

ENERGY STAR sets window criteria by climate zone, based on ratings from the National Fenestration Rating Council (NFRC) ⁷. Maryland's 23 counties and Baltimore City fall into two zones (ENERGY STAR climate zone finder) ⁶:

Every ENERGY STAR window must also meet an air leakage limit of 0.3 cubic feet per minute per square foot ⁵. In the Northern zone, the criteria also accept U-factors of 0.23 to 0.26 when paired with a higher SHGC: 0.35 or more for 0.23 and 0.24, and 0.40 or more for 0.25 and 0.26 ⁵.

What the numbers mean in a mixed climate

U-factor measures how fast heat moves through the whole window. A lower number insulates better. The North-Central zone, which covers nearly every Maryland home, asks for 0.25 or less ⁵.

SHGC (solar heat gain coefficient) is the share of the sun's heat that passes through the glass. In the North-Central zone ENERGY STAR caps it at 0.40 ⁵. That is a middle setting: Maryland houses need heating in winter and cooling in humid summers, so the criteria limit solar heat without asking for the very low SHGC of the southern zones, which is 0.23 or less ⁵.

In Cumberland, Frostburg and the rest of Allegany and Garrett counties, the Northern zone applies: the U-factor limit tightens to 0.22, and SHGC becomes a minimum of 0.17 rather than a cap, because winter sun is useful heat there ⁵⁶.

Questions for a Maryland quote

• What are the NFRC-rated U-factor and SHGC of the exact window quoted, and do they meet ENERGY STAR's criteria for your county's zone?
• Is the low-E coating the same on every side of the house, or tuned for the west- and south-facing windows that take the afternoon sun? The low-E glass article explains the options.
• How does the U-factor of the quoted window compare with a second quote's, for the same size and style?
• How will the gap between the frame and the wall opening be sealed against summer humidity and winter drafts?

The energy-efficient windows explainer covers the ratings in more depth.

Cost, permits and next steps

Maryland prices follow the same drivers as anywhere: the number of windows, frame material, glass package, full-frame or insert installation, and labor. This article does not quote Maryland or city prices, because the national surveys do not publish reliable state figures. The window replacement cost guide sets the national surveys side by side.

Whether your job needs a building permit depends on your county or city, and the article on window replacement permits explains why answers differ. Ask the installer who will pull any permit and whether its cost is included in the quote.

When you are ready, you can compare quotes from window installers.

About these figures

• ¹ Official record: Maryland Home Improvement Commission page (licensing of contractors and salespersons, the definition of home improvement and its condominium and four-unit exclusions, the July 1, 2016 end of the subcontractor license, and that only licensed contractors may contract with homeowners), checked October 26, 2026.
• ² Official record: MHIC list of work that usually requires an MHIC license (windows, storm windows, window tinting), checked October 26, 2026.
• ³ Official record: MHIC Home Improvement Public Query (search options for active licensees and the note on disciplinary information), checked October 26, 2026.
• ⁴ Official record: MHIC contracts page (required contract contents, the 1/3 deposit limit, the arbitration clause rules, and the Door-to-Door Sales Act cancellation periods of five business days, or seven days for buyers 65 and older), checked October 26, 2026.
• ⁵ Official record: ENERGY STAR window criteria for the Northern, North-Central and Southern zones, including the equivalent-performance options and air leakage 0.3, checked October 26, 2026.
• ⁶ Official record: ENERGY STAR county climate zone spreadsheet for Maryland (Baltimore City and 23 counties: Baltimore City and 21 counties North-Central, 2 counties Northern), checked October 26, 2026.
• ⁷ Official record: ENERGY STAR statement that window criteria rest on NFRC ratings and vary by climate zone, checked October 26, 2026.
• ⁸ Official record: MHIC FAQ answer that interior window treatments are decorating and not home improvement, checked October 26, 2026.