Timekeeping and payroll are usually bought years apart and then asked to behave as one system. The join between them produces a surprising share of payroll errors, and almost none of them are arithmetic. They are timing problems: a correction after the cut off, an approval nobody gave, a week still open when the file was produced.
Where it breaks, in order of frequency
A correction after the cut off, a new starter who exists in one system and not the other, a leaver whose final week is short, and a pay rate that changed mid period. Every one is a synchronisation problem rather than a calculation problem, which is why more software rarely fixes it and a short written sequence usually does.
Make approval a gate
Hours should not reach payroll unapproved. If the product allows an unapproved week to export, somebody eventually will, and the first anybody hears of it is the person whose pay is short. Approval should be recorded against a named person and a time, because that record is what makes a disputed week answerable.
Agree the retro rule once
Late corrections are inevitable. Decide that they are paid as a labelled adjustment in the next period, make sure both systems describe them the same way, and stop negotiating it case by case. Consistency here is what makes a payslip explainable when somebody queries it months later.
Questions people ask about timekeeping and payroll
Should timekeeping and payroll be one product?
It removes the file and the timing risk and constrains you to one vendor's strengths. Where payroll sits with an accountant, the decision is largely made for you.
What is the commonest cause of a pay error?
Unapproved or late hours reaching payroll. It is a process control rather than a software feature.
Can pay periods differ between the two?
They can and it doubles the cut offs somebody manages. Aligning them is usually worth more than any feature.