Re: Significant barrier?
"If you are homeless, you can still register to vote even if you don’t have a fixed address.
To apply to register, you will need to fill in a form which is available to download from
https://www.gov.uk/government/publications/voter-registration-forms-paper-versions
or it can be requested from your local electoral registration office.
You can find contact details for your local electoral office at www.yourvotematters.co.uk
The form asks you for an address where you want to be registered. This can be anywhere in the local authority area where you spend a substantial part of your time or have some connection with, for example, a previous permanent address, a shelter or a park bench. You will be assigned to a polling station near to this address to vote on polling day.
The form also asks for an address where you can be sent correspondence and your poll card. Alternatively you can opt to pick this up from your local authority."
Source: https://www.electoralcommission.org.uk/__data/assets/pdf_file/0009/223101/Registering_to_Vote2017.pdf