In most cases you will not need a licence to hold a street party but you will need to notify Suffolk County Council if you intend to hold one (phone 0345 6069 6171).
If you plan to sell alcohol or provide entertainment to the wider community (not just your neighbourhood) then you may need a Temporary Events Notice (TEN)
If you want to close the road you will need to apply to Suffolk County Council. Closing a no-through road needs six weeks notice and an event order (closing a through road) needs at least three months notice.
You can find more help and advice about street parties from The Street Party site
You will need to send your notification to the council where your street party will be held. If you do not know who this it, visit: Gov.UK, find your local council
An application to notify Suffolk County Council is in the guide to organising street parties.