What happens if the pre-funding invoice is higher than the actual payroll?

First of all, the pre-funding invoice does not include every payroll item; for example, local severance accruals or pension contributions are not captured in the pre-funding invoice. In addition, your monthly Oyster fee is only charged in the settlement invoice. 

This means we err on the side of underestimating the pre-funding invoice so that you don’t pay more than the actual amount. In the unlikely case that we overcharge you at pre-funding, you can rest assured that a refund will be initiated at the earliest through the settlement invoice.