The City counts anyone paid on a 1099 by Philadelphia clients as a business. From tax year 2025 the $100,000 BIRT exemption is gone: every business files the Business Income & Receipts Tax - 1.410 mills on Philadelphia gross receipts and 5.71% on taxable net income for 2025 - by April 15. An unincorporated business also files the Net Profits Tax (3.74% for residents, 3.43% for non-residents, 1.5% with the income-based reduction and a Pennsylvania Schedule SP) and takes a credit of 60% of the BIRT net-income portion against it. A return is filed even when no tax is due.
With each year's returns comes the next year's estimates: the BIRT estimate, 100% of this year's BIRT, by April 15 (a first-time filer for tax year 2025 does not pay it with that first return), and two NPT estimates, each 25% of this year's NPT, on April 15 and June 15. There are no extensions for paying.