21st Century Accounting

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Click Hot Topics for current issues! For information related to COVID-19 issues, click here.

Technical Support Hours: Monday-Friday 10:00 AM-4:00 PM CST Open an Incident Closed January 18, 2021 for MLK Day

Existing customers: Need help finding your Serial Number, Version Number, or installed add-ons? Click here.

New customers: register your software now to ensure that you receive updates!

Address or email change? Please let us know here.

Hot Topics

  • COVID-19 Information
  • Changes to Federal Income Tax for 2020
  • Download September 30, 2020 Payroll Tax Update - Does not include 2020 W-4 configuration
  • North Dakota SIT Configuration Information
  • C21 Tips for Efficient Payroll
  • Hardware Requirements
  • Moving to a new computer
  • Converting to C21
  • Social Security Duplication Patch to allow multiple employees with same SSN
  • Technical Support Subscription
  • Affordable Care Act (ACA) support
  • Supported Tax Forms
  • What if my W-2 does not line up correctly on my store bought printed forms?
  • Pervasive PSQL and Network Permissions
  • 2013 Additional Medicare Tax
  • Email invoices and statements
  • Email reports
  • Email Direct Deposit Advices
  • Electronic Funds Transfer
  • Implementing Paid Sick Leave for California's Healthy Workplace Law
  • Customize Tax Forms
  • Instructions for Data Recovery

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