Difference time between United kingdom and United States of America in hours, minutes, and seconds is [ +4 hours ] with gregorian date today is Saturday 21st of March 2026 in British local time, Where the time now in United kingdom is 00:45 AM and the time now in United States of America is 20:45 PM in American local time and the time comparison between United Kingdom of Great Britain & Northern Ireland and United States of America in greenwich time ( GMT ) where United kingdom advanced about greenwich time ( GMT +01:00 ) while United States of America late for greenwich time ( GMT -04:00 ).