USA Payroll has found these web sites to be helpful.
Tax Facts
- 2022 Tax Facts (PDF)
- 2021 Tax Facts (PDF)
- 2020 Tax Facts (PDF)
Federal
- Internal Revenue Service
- FAQs for 2020 W-4
- W-4 Form (2020)
- Employee Tax Withholding Estimator
- Understanding the 2020 Form W-4 and How to Use it to Calculate Withholding (hour-and-ten-minute-long video with transcript)
- 2020 W-4 Guide for Evolution (PDF)
- Social Security Administration
- US Department of Labor
- W-4 Form (pre-2020)
- I9 Form
- W9 Request for Taxpayer ID Number
- CDC COVID-19
New Jersey
Pennsylvania
- PA Department of Revenue
- PA Department of Labor and Industry
- Act 32 EIT Collection System
- PA Local Withholding Rates by Address
- PA Residency Certification Form
Delaware
Philadelphia
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