Sales Tax on a Florida Steel Building: What to Confirm Before the First Invoice

The first invoice should follow the actual steel-building transaction. Selling a kit and delivering it is different from completing a permanent improvement to real property, and the contract label alone does not settle the answer.

Use this review for the specific building you are about to bill. The broader Florida contractor sales-tax guide explains the general framework.

Identify What You Are Delivering

If you sell and deliver a prefabricated steel building without installing it, the transaction is generally a taxable sale of tangible personal property, absent an applicable exemption. Confirm the delivery location, the purchaser, and any exemption documentation before setting the tax line.

If you supply and install the building, determine whether the completed work becomes an improvement to real property. Review the attachment, intended use, and actual scope. Installation by itself is not a universal tax exemption; a movable structure or a sale of personal property with installation needs its own classification.

Florida's general state sales-tax rate is 6%, with applicable county discretionary surtax. The Florida Department of Revenue sales-tax guidance explains the distinction between sales tax and use tax.

Match the Purchase Records to the Contract

For ordinary lump-sum, cost-plus or fixed-fee, guaranteed-price, and time-and-materials contracts to improve real property, the contractor generally consumes the materials. Tax belongs on the contractor's taxable purchases rather than on the completed improvement billed to the owner.

Check the supplier invoices, resale purchases withdrawn for the job, and out-of-state purchases. If the supplier did not collect the required tax, a use-tax obligation may remain. Do not add customer sales tax simply to compensate for an untaxed materials purchase.

If your business fabricates components in its own shop for installation, review fabrication-cost use tax as well. Tax paid on raw steel does not necessarily settle the full obligation. The Department's building-contractor guidance addresses contractor purchases, fabrication, and resale withdrawals.

Test Any Retail-Sale-Plus-Installation Claim

A separate materials line on the final invoice does not by itself create this contract type. Confirm that the agreement describes, itemizes, and prices all materials and supplies before work begins, separately prices the installation, and provides for the purchaser to assume title and risk of loss as the items are delivered.

Florida's Technical Assistance Advisement 24A-018 discusses these requirements, including incidental installation supplies. It is advice tied to that taxpayer's facts, not a blanket approval of other contracts.

Under a qualifying retail-sale-plus-installation arrangement, the materials are retail sales and the tax treatment differs from an ordinary real-property contract. Resolve the classification before purchasing and billing; do not try to create it retroactively by changing invoice labels.

Confirm the County and the Surtax Base

The state rate and county surtax do not necessarily apply to the same dollar base. Florida generally limits discretionary surtax to the first $5,000 of a qualifying item of tangible personal property. That is not a $5,000 cap on the state sales-tax base.

For a multi-part building kit, determine whether the single-sale and working-unit rules allow the components to be treated as one item. Do not assume the whole project is one item merely because it has one invoice.

The Department addressed prefabricated steel buildings specifically in Technical Assistance Advisement 26A-001: the surtax limitation depended on satisfying those tests. Its conclusions are limited to the described facts. Use the Department's address lookup and the applicable sourcing rules to confirm the county rather than copying the previous job's rate.

Assemble the Invoice Review Packet

Before the first bill goes out, put these records together:

• Signed scope showing delivery only or installation, with the building specifications.
• Contract pricing, title-transfer, and risk-of-loss terms.
• Delivery and jobsite addresses.
• Supplier tax records and any documented exemption or resale treatment.
• Fabrication details, if you manufacture components for the job.
• The proposed invoice and the reason for its sales-tax treatment.

KDM Accounting Services can help review the bookkeeping and tax treatment against that file. If the contract does not clearly establish the arrangement, resolve its terms with the appropriate adviser before billing. Contact KDM for help reviewing the transaction, and use the first-invoice checklist for the surrounding business records.