Free Interior Designer Invoice Template & Generator

Interior Design Invoicing by the Numbers

Interior designers juggle deposits, procurement, and final installs, so clear invoicing keeps each project's cash flow on track. Slow client payments are a real risk: 56% of US small businesses are owed money from unpaid invoices, averaging about $17,500 each, and 47% report invoices overdue by more than 30 days, according to the Intuit QuickBooks 2025 US Small Business Late Payments Report. That strain shows up across the sector, where 51% of small employer firms cite uneven cash flow as a financial challenge, per the Federal Reserve Banks' 2025 Report on Employer Firms. Designers can collect faster, too: invoices offering convenient online payment options get paid up to twice as fast, according to Xero (2024).

What every interior designer invoice needs

Separate your design fee from product costs and procurement markup so clients understand what they're paying for. Design time is often billed hourly or as a flat room/project fee, while furnishings are billed at cost plus a markup or your trade-discount margin. Include the project or room name, a clear line for any deposit applied, and note that taxable goods (furniture, materials) may carry sales tax even when design services don't.

Hourly, flat-fee, and cost-plus billing

Interior designers commonly mix billing models: hourly (often $75–$250/hr) for design and consultation, a flat fee for a defined scope, and cost-plus for furnishings where you add a markup to wholesale prices. State which model applies to each line so clients see the logic. Bill milestone deposits up front for procurement, since you often pay vendors before the client reimburses you, and show the remaining balance after each draw.

How do interior designers structure their invoices?

Most designers split the invoice into design fees and furnishings. Design time is billed hourly or as a flat project fee, while products are billed at cost plus a markup or your trade margin. List the project or room, apply any deposit, and keep service fees separate from taxable goods. This makes the invoice transparent and easy for clients to approve.

Do interior designers charge sales tax?

Design services are not taxable in many U.S. states, but tangible goods like furniture, fabric, and materials usually are. If you purchase and resell furnishings to a client, you typically collect sales tax on those goods at your state's rate, often using a resale certificate when buying wholesale. Confirm your state's rules and add a tax line only to the taxable product portion of the invoice.

Should I require a deposit before starting a design project?

Yes. Most interior designers collect a retainer or deposit before beginning work, and a separate procurement deposit before ordering furnishings, since vendors often require payment up front. Show the deposit applied against the total on each invoice and bill the remaining balance at agreed milestones. This protects your cash flow and limits your exposure on goods you've already paid for.