Changes to UK border policy from the 1st of Oct 2021.
What you need to enter the UK If you’re an EU, EEA or Swiss citizen
Irish citizens can continue to enter and live in the UK.
EU, EEA and Swiss citizens can travel to the UK for holidays or short trips without needing a visa. You can cross the UK border using a valid passport which should be valid for the whole time you are in the UK.
You will not be able to use an EU, EEA or Swiss national ID card to enter the UK from 1 October 2021 unless you:
In these cases, you can continue to use your national ID card to enter the UK until at least 31 December 2025.
You must have the correct documents to show at the UK border if you’re travelling to the UK. You cannot use any documents to enter the UK that are not listed here.
If you’re a non-EEA family member of an EU, EEA or Swiss citizen
You need a valid national passport, and one of the following
an EU Settlement Scheme family permit
a UK-issued EEA family permit
a UK-issued biometric residence card
You cannot use an Article 10 or Article 20 residence card issued by an EEA member state.
Business travel to the UK
If you’re an EU, EEA or Swiss Citizen travelling to the UK for a short business trip, you may not need to apply for a visa.
Under the UK’s new points-based immigration system, you can continue to visit the UK without applying for a visa. In most cases you can stay for up to 6 months. You may participate in a wide range of activities including business-related activities such as meetings, events and conferences. You may enter the UK multiple times during that period but you may not live in the UK by means of frequent or successive visits.
As a business visitor, you cannot:
do paid or unpaid work for a UK company or as a self-employed person
do a work placement or internship
sell directly to the public or provide goods and services
You can read more details on the UK Goverment website Here.