score:5
According to https://www.gov.uk/guidance/visiting-the-uk-after-brexit
What you'll need to do to visit the UK after the UK leaves the EU, including whether you'll need to apply for a visa.
If the UK leaves the EU with a deal
If the UK leaves the EU with a deal, what youβll need to enter the UK will not change until 2021.
If the UK leaves the EU without a deal
EU, EEA and Swiss citizens will be able to enter the UK as they do now after 31 October 2019.
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What you need to show at the UK border
What you need to show at the UK border will not change immediately if the UK leaves the EU without a deal.
Youβll need to show a valid passport or national identity card if youβre a citizen of either:
- an EU country
- Iceland, Liechtenstein, Norway or Switzerland
EEA national identity cards will be phased out for travel to the UK during 2020. More details will be provided shortly.
How long will we be allowed to stay in the UK for a holiday?
At a minimum, I would expect a visitor from the EU would be able to stay for up to 90 days in any 180-day period. That seems to be the general guidance. Many sources talk about 6 months in any year but as far as I know the officers at the border don't use a fixed time limit, they assess whether you are attempting to make the UK your home. You should be ok long as you have supporting documents to show that you can support yourselves financially and that you have good reasons to return home (jobs, homes, family etc).
Will we need a passport or will our Germany IDs be enough?
A national ID card should be enough in 2020.
Will we need to apply for a visa beforehand?
Someone visiting the UK today from non-EU countries like Norway do not need a visa. It seems to me very unlikely that the UK would treat EU citizens less favourably than Norwegian citizens even after a no-deal Brexit. You won't need a visa in 2020.