England are the favourites to win the Six Nations after an opening win against Italy.
However, Ireland are closing in after an impressive opening two matches.
Bet365 make England odds-on to win, at 4/5.
Ireland, who opened the tournament with an away with at France, are second favourites, at 6/5.
Both have won their opening two matches of the tournament.
England are also considered the most likely Grand Slam winner, although it is odds-against anyone completing a clean sweep.
Skybet make England 2/1 to do the Grand Slam again.
Ireland are 3/1.
In terms of the Triple Crown, Endland are 13/10 while it is 5/2 that there will be no winner.