I assume that:You are a US citizen or resident alien.You are performing this service in the US.You are not considered to be an employee of the entity for which you are performing this service.With those assumptions: You file Schedule C with your tax return, claiming the gross income from the freelance project and taking any deductions related to the generation of that income - such as supplies that you purchased specifically for that project. The instructions for Schedule C can be found at http://www.irs.gov/pub/irs-pdf/i....If your net income from the project is $400 or more, you must also file Schedule SE and pay an additional tax on the net income. The instructions for Schedule SE can be found at http://www.irs.gov/pub/irs-pdf/i....I also recommend that you take a look at IRS Publication 334, Tax Guide for Small Business, http://www.irs.gov/pub/irs-pdf/p.... IRS Publication 535, Business Expenses (http://www.irs.gov/pub/irs-pdf/p...) and IRS Publication 583, Starting a Business and Keeping Records (http://www.irs.gov/pub/irs-pdf/p...), may also be useful to you.If this sounds like overkill for a small freelance project - well, maybe it is, but I expect that as you progress in your career more of these little projects will be coming your way, and it's a good idea to learn as much as you can now so that you can plan ahead for what may come your way in the future.