Generally, your startup costs are deductible, even if you don't make sales or turn a profit immediately. However, the time frame for deducting expenses (and the amount you can deduct) can depend on the form of legal entity you have chosen. This really is a tax question, and you should be sure to speak to an accountant who understands small business tax issues.
Often entrepreneurs don't have the core competencies to understand accounting, which could result in a startup failing. Here is how an entrepreneur should approach hiring an accountant or outsourcing her financial tasks to ensure success.