England's victory over Italy means a win against Wales in Cardiff next Saturday would seal a first Grand Slam in a decade.
However, Wales have everything to play for because a victory for them could be enough to retain the RBS 6 Nations title and leave England empty-handed.
England are currently two points ahead of Wales in the table and with a points-difference advantage of 14.
Under tournament rules, if the points and points difference end level then the championship would be decided on tries scored. Wales hold the advantage 7-5 going into the final round. If tries scored is also level, the title is shared.
Here, Press Association Sport examines the permutations:
ENGLAND WIN GRAND SLAM
:: An England victory by any margin would secure a first Grand Slam triumph in a decade.
ENGLAND WIN TITLE
:: An England defeat by six points or fewer would still be enough to seal the title.
:: If England lose by seven points but outscore Wales by three tries or more then Stuart Lancaster's men would win the title.
WALES WIN TITLE
:: A Wales victory by seven points, providing they stay ahead of England on tournament tries, would see Rob Howley's men retain the title.
:: If Wales win by seven points but England score two more tries then the title would be shared.