Payroll ran, employees got paid, deposits went out on schedule, and the agency’s balance still does not match what you think you paid. That gap is rarely random. Here is why it happens, the five most common causes, and how to trace yours.

"We thought payroll was handling this" is one of the most common lines businesses say after a notice arrives, and it's usually true, payroll was running fine. The problem is that payroll processing and payroll compliance are not the same function, and registrations, work states, and filings depend on information the provider was never given. Here's why these gaps slip past even a provider that's doing its job correctly, and who actually owns closing them.

Most multi-state payroll mistakes aren't the result of bad intentions, they happen because growth outpaces internal process. This guide walks through the nine most common ones, from assuming processing means compliance to carrying old problems through a provider transition, and what to check before each one turns into a notice.

Hiring someone who works in a new state almost always creates payroll tax obligations you didn't have before, and payroll keeps running whether or not it's handled. Here's what to check right after the hire.