Officials at Aintree have announced next year's Crabbie's Grand National will be run at 5.15pm.
Nearly nine million viewers watched on Channel 4 this year as Leighton Aspell steered the Oliver Sherwood-trained Many Clouds to victory after the race started at 4.15pm.
However, Aintree and Channel 4 hope the change to the start time will help to further increase the audience for the famous race, with research suggesting pushing the start back by an hour may help to maximise interest.
John Baker, who runs Aintree as the regional director of the Jockey Club North West, said: "This is a very positive move for the Crabbie's Grand National and we're excited about the possibility of showcasing the greatest chase in the world to a wider national and global audience.
"The Crabbie's Grand National is in a great place and we're already delighted to be Channel 4's biggest audience of the year at 8.9 million viewers, which is a fantastic figure, but any increase is also good for the sport.
"We're always keen to explore ways to grow and enhance this superb three-day festival and we believe that in collaboration with our broadcast partner, Channel 4, and with the backing of the BHA, this is another extremely positive step forward for the 'People's Race'."
The change means a handicap hurdle for conditional and amateur jockeys will now be the only race which will follow the Grand National while in previous years there has also been a bumper at the end of the card.
Ed Havard, Channel 4's head of TV events, has hailed the switch as a positive move.
He said: "The Grand National is one of the greatest sporting occasions in the world and one of the most-watched TV events of the year.
"This move will place the National as the fitting climax of the three-day festival, showcasing the race for the widest possible audience and in the most spectacular fashion."
The 5.15pm slot follows afternoon live football and the results round-up on BBC Radio 5 Live, with officials hoping the change will give more people the opportunity to tune in.
Richard Burgess, head of BBC radio sport, said: "We look forward to providing extensive build-up and uninterrupted commentary on BBC Radio 5 Live of the Grand National in its new time slot."