The changes you need to report

If the date your employee stops working is different from the date stated on the A1 (certificate of coverage), please let us know. We will check whether a new certificate is necessary.

Please report the change in the end date to us online via TWinternet.

• Log in to your account via Twinternet using eHerkenning
• Click on Overview A1 (E)101 certificates
• Click on Changes
• Change the end date for certificates that have already been approved

It is only possible to change the end date for a group of employees if the end date is the same for the whole group.

• Select the employees who should get the same end date
• Click on Change the work period for the selected persons
• Fill in the new end date

Extending a posting period

It is only possible to extend an A1 (certificate of coverage) if the total posting period is not longer than 2 years. If the period is longer than 2 years, you will need to make a new application.

Changing the start date

If you want to change the start date of an A1 (certificate of coverage), you will need to make a new application.

If your employee moves to a new address and becomes insured in another country as a result, we will inform you of this. If your employee's social insurance situation does not change and they are still insured in the Netherlands, they will get a new A1 (certificate of coverage) with their new address.

If you have any questions about this, you can contact us.

If your employee is going to work less than 25% of their total working time in the country where they live, you must inform us of this. If it means that your employee's insurance will switch to another country, we will let you know.

If your company’s payroll tax number changes, please let us know. We can then check to see whether we need to issue a new certificate.

Remember to apply for a new account via TWinternet if your company gets a new payroll tax number.

You must inform us if there is any change to a posting period.

You must inform us if you move to a new address. If your change of address means you become insured in another country, we will let you know. If you are still insured in the Netherlands, you will get a new A1 (certificate of coverage) with your new address.

If you are going to work less than 25% of your total working hours in the country where you live, you must inform us of this. If it means that your insurance will switch to another country, we will let you know.