Michigan HVAC Business Registration — LLC, EIN, and Tax Setup for Contractors

Getting Your License Is Step One — Forming the Business Is Step Two

Passing the PSI exam and getting your Mechanical Contractor license from LARA doesn't mean you can start pulling permits and sending invoices the next day. Before operating, set up the business, tax, and employer accounts that apply to your structure and activities. Skip an applicable step and you'll hit walls at the municipal level — local building departments may require proof of business registration and tax accounts before they'll activate your permit access.

Forming Your Business Entity

Most Michigan HVAC contractors form a limited liability company (LLC) because it generally separates personal assets from business liabilities. If a job goes wrong and a lawsuit follows, an LLC usually limits the plaintiff to the company's assets, but personal guarantees and the owner's own conduct can still create personal exposure.

To form a Michigan LLC:

1. File Articles of Organization with LARA's Corporations Division (not the Bureau of Construction Codes — different division, same agency). The filing fee is $50.
2. Choose a registered agent — this can be yourself at your business address or a commercial registered agent service. The agent receives legal documents on behalf of the LLC.
3. Draft an Operating Agreement — not legally required in Michigan, but essential if you have partners or want clear internal rules about profit distribution, decision-making, and what happens if a member exits.

Sole proprietorships and corporations are also options, but the LLC is the most common structure for trade contractors because of its liability protection and pass-through tax treatment.

Federal EIN Registration

Many HVAC businesses obtain a Federal Employer Identification Number (EIN) from the IRS. A single-member LLC with no employees and no excise-tax filing obligation generally does not need a separate federal EIN, although it may obtain one for banking or state and local requirements. Partnerships, corporations, and businesses with employees generally need one. The EIN is your business's tax identity — you'll use it for:

• Opening a business bank account
• Filing federal tax returns when the entity is required to use an EIN
• Registering with Michigan's state tax systems when required
• Local building department permit applications (Grand Rapids, for example, requires your Federal EIN on the contractor registration form)

Apply online at the IRS website. It's free and immediate — you receive your EIN at the end of the online application. Avoid third-party services that charge fees for what the IRS provides at no cost.

Michigan Treasury Online (MTO) Tax Registration

Businesses with applicable state tax obligations register through Michigan Treasury Online (MTO). For HVAC contractors, the relevant accounts are:

• Sales and Use Tax — Michigan levies a 6% sales tax. For real-property work, contractors generally are the consumers of taxable materials and equipment used and must pay applicable sales or use tax; they generally don't charge sales tax separately to the customer for the labor and materials incorporated into the real property.
• Withholding Tax — Required once you hire employees. You'll withhold Michigan income tax from their paychecks and remit it to the state.
• Corporate Income Tax — If you're structured as a C-corporation. LLCs with pass-through taxation file through their members' individual returns instead.

Register through the MTO portal. The system assigns your state tax account numbers, which you'll reference on required filings.

Unemployment Insurance Agency (UIA)

You must register with the Unemployment Insurance Agency through MiWAM (Michigan Web Account Manager) when your business becomes a liable employer — generally when it pays $1,000 or more in covered wages in a calendar year or employs at least one person in 20 different weeks in a calendar year.

UIA registration triggers your obligation to pay unemployment insurance tax on wages. For 2026, UIA lists a 2.7% new-employer rate generally and a 5.0% construction rate; the taxable wage base for qualified employers is $9,000. Rates and wage bases can change.

A business with no employees generally has no UIA employer registration obligation, but once you hire workers, track the $1,000 and 20-week thresholds and register when liability attaches. Don't wait until you've been paying someone for months — the state assesses penalties for late registration, and local building departments in cities like Warren and Grand Rapids ask for your MESC employer number when you apply for contractor registration.

The Registration Sequence Matters

These registrations have a logical order, and doing them out of sequence creates problems:

1. Form the LLC (you need the entity name for everything else)
2. Get an EIN if your entity or state/local setup requires one (many contractors obtain it for tax accounts and local registration)
3. Register on MTO (use the EIN if your setup requires or has one)
4. Register with UIA when the liability thresholds above apply
5. Register your state mechanical license with local building departments (they may ask for proof of the applicable items above)

The Michigan HVAC License Guide maps out this entire compliance sequence — from LARA licensing through business formation, tax registration, and local municipal activation — so nothing falls through the cracks.

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