Design fees: flat, hourly, or by square foot
Interior designers structure fees in a few recognizable ways, and your invoice should state which model this project uses. A flat design fee is quoted for the whole scope and often billed in phases (concept, development, and installation), so show the phase this invoice covers and the amount. Hourly billing lists your rate and the hours worked, ideally broken out by activity like site visits, sourcing, drawings, and client meetings so the time reads clearly. Some designers price the design fee per square foot of the space being designed. Whichever model you use, keep the design fee on its own set of lines, separate from any product costs, so the client can tell professional services apart from furnishings. This free template lets you mix flat, hourly, and per-square-foot lines with no sign-up.
Procurement, markup, and trade pricing
Furnishings are where interior design invoices get their own character. When you procure furniture, lighting, textiles, and decor on the client's behalf, you usually buy at trade or net pricing and bill the client at retail, or apply a stated markup on your net cost; that spread is a normal part of how designers earn on product. Decide whether to show items at the client price with your margin built in, or to show net cost plus a visible markup percentage, and be consistent across the project. Itemize each piece with a description, quantity, and price, and add shipping, freight, receiving, and white-glove delivery as their own lines because those costs are real and clients expect to see them. Keep procurement clearly separate from your design fee so the two revenue streams never blur together. Every line is editable and exports to PDF or Word.
Deposits, retainers, and payment terms
Interior design projects almost always start with money up front. Many designers collect a retainer or an initial design-fee deposit before work begins and draw against it, while product orders require a deposit of the full item cost since vendors need payment to place the order; show these as credits against the relevant balance. Reimbursable expenses like samples, delivery, and travel are passed through and itemized. Bill in phases so the client pays as the project moves rather than one large sum at the end. Sales tax on furnishings is common and often applies to the product side but not the design service, so apply the tax line only to taxable goods and label the rate. Include your accepted payment methods, deposit terms, and a note on when final installation is due. The template is free, customizable, and needs no account.