You should understand SAS-70 compliance. You should have worked in most capacities in payroll in the past. You should be a Certified Payroll Professional. Your company should also have an Enrolled Agent on site with several years of payroll experience.
Off the top of my head it would be helpful to know about benefits in kind, tax credits, tax codes depending on what services you are offering but you're likely to be asked about those.
It would be best to have worked in payroll but I wouldn't say impossible without having done so. I would say that if you haven't worked in the role, then formal study is advisable.
I'm sure I will have missed out something obvious but here's a few links
I remember that Lisa (LaShell Bookkeeping) was a bit of a Payroll Whizz and she spoke about doing the IPP exams (Chartered Institute of Payroll Professionals) with Holmes Training.
But ignore all of the AAT stuff as it's now defunct info as discussed above.
I always feel that Payroll is one of those area's where comparative to bookkeeping and accounts there really isn't the depth of learning to justify the amounts that some training providers charge in this area. However, on the flip side it's an area where, unlike bookkeeping, the training providers are going to need to rewrite / replace their manuals every year and they've got to recoupe that somehow.
I think that few peope that work in Payroll actually have qualifications in it. I used to be responsible for the weekly payment of 350,000 people and in my department nobody had a payroll related qualification but we all knew exactly what we were doing.
That said, where there's a need there's a professional body wanting to relieve you of your money so if you need a qualification I would say that the IPP one is the qualification of choice.
HTH,
Shaun.
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Shaun
Responses are not meant as a substitute for professional advice. Answers are intended as outline only the advice of a qualified professional with access to all relevant information should be sought before acting on any response given.