Personal tax – form

National Insurance: apply for an E101 if self-employed in European Economic Area (CA3837)

Use the online service or postal form to apply for form E101 to confirm you remain in the UK National Insurance scheme.



If you’re normally self-employed in the UK and going to work temporarily in another country within the European Economic Area, apply for form E101 to confirm you remain in the UK National Insurance scheme.

Use the online service (sign-in or set up a Government Gateway account)

You may need to give HMRC additional information to support this form. Fill in and submit this form online but send any additional information to us by post. You’ll be given a unique reference number when you submit the form. Include this number with the additional information you send by post (address below). You can track the progress of the form online using the same reference number.

Fill in form on-screen, print and post to HM Revenue and Customs (HMRC)

Instead of applying online, you can download this form, fill it in and send it to us along with the additional information. If you submit the form this way, you can’t track its progress online.

send your form and any additional information to:

HM Revenue and Customs
United Kingdom

You’ll need to fill in the form fully before you can print it. You can’t save a partly completed form so you should gather all your information together before you start to fill it in.

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This form will help HM Revenue and Customs to determine which member state’s social security legislation will apply. If you normally work in 2 or more EEA countries you should fill in form CA8421i instead.

Applicable countries:

Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, United Kingdom

EEA nationals

If you’re an EEA national, social security liability is determined by EC Regulation 883/04.

Non–EEA nationals

If you aren’t an EEA national, but are legally resident in a European Union Member State, social security legislation is determined by EC Regulation 1408/71