atdwelcome - Time Management Systems

Welcome ATD Customers!

Dear American Time Data Customer,

We at Time Management Systems are extremely excited for the opportunity to partner with American Time Data to serve you better! TMS is one of the largest Attendance Enterprise vendors in the country backed by our unbeatable customer support team. Whether you call, email or request onsite assistance, TMS/ATD local representation will accommodate your needs. To get acquainted, we have included the information below about who we are as a company and what you can expect from us.


Mindy Kroll, CEO | Time Management Systems

About TMS

Time Management Systems was founded by Carol Rademacher in Sioux City, IA in 1985. Fast forward nearly 35 years and TMS is still family-owned and operated. Now owned by Carol’s daughters, Jen Vanderloo (CFO) and Mindy Kroll (CEO), TMS’ goal is still the same; to offer Unbeatable Customer Support, along with the finest Time and Attendance systems.

Our 26 member team supports well over 6,000 customers, ranging from 5 to 10,000 employees. To better serve our customer base, TMS has four locations: Sioux City, Iowa; Sioux Falls, South Dakota; Dania Beach, Florida; and Columbia, South Carolina.

Time Management Systems has expanded beyond Time and Attendance in recent years, now offering Payroll and Security divisions. Our cloud-based Time and Attendance software, tmsConneXion fully integrates all of our divisions on one website platform for the ultimate convenience.

Our Service Team…

ready to serve your support needs

Our highly skilled technicians provide service in a variety of ways; via telephone, remote desktop support, or on-site if needed. This flexibility ensures the fastest response to customer’s needs. Our service team consists of:


Nishanth Kannan – Director of Customer Support

9 Support Specialists, 6 Project Specialists,

I.T. Specialist, Application Developer


605-271-7124 |

For any questions or more information, Contact either:

Mindy Kroll

605-306-5535 |

Rebecca Patterson

803-791-8463 |