As of 1 January 2013 the Dutch Sickness Benefits Act (Ziektewet, ZW) has changed. Instead of paying a sector premium, large and mid-sized employers now pay a ZW premium that increases with the number of their own employees who flow into the ZW (premium differentiation). In addition, people receiving sickness benefits will now be reassessed after 52 weeks of illness. If the reassessment shows that they are able to earn 65 percent or more of their last earned salary the sickness benefits will be stopped.

Thanks to the premium differentiation, temporary agency workers flow out of the ZW more rapidly. In addition, they are placed with their previous employer (the temporary employment agency) more often. As a result, an additional 7,500 temporary agency workers were working on 1 January 2016. The inflow into the ZW from the agency sector is not decreasing. There is no strong evidence that premium differentiation leads to risk selection or the passing on of risks.

Also, the one-year reassessment under the Sickness Benefits Act results in a more rapid outflow from sickness benefits. This has led to a decreased inflow into the WIA (Work and Income (Capacity for Work) Act). On 1 January 2016 the number of WIA benefits had decreased by 1,450 due to the one-year reassessment under the Sickness Benefits Act.