The Bannockburn Live commemoration of the two-day battle will feature replays of the fighting and have performers including Brave singer Julie Fowlis at the site of the bloody exchanges.
Following the weekend's events on June 28 and 29, tourism body VisitScotland is to treat 39 clans to an exclusive day in the new £9 million Bannockburn Visitor Centre and the re-enactment field in Stirling free of charge as compensation for the scaling back of the main anniversary showcase.
A source said the Monday event is "a special thank-you to the clans for all their support surrounding this event and others".
As well as VisitScotland picking up the bill for the free clans day, the Clanranald Trust, which is conducting the re-enactments, is also to do battle shows free of charge.
Malin Heen-Allan, of Clanranald Trust, said actor-warriors from across the globe including Germany, Denmark, Poland - and England - are rehearsing in Scotland for the replay.
She said: "The challenge is to put a 48-hour battle into 30 minutes. It will be more of a battle show than a re-enactment.
"We will also have activities in the village from fletchers to blacksmiths."
The Council of Scottish Clans and Associations, with clan representatives from across North America, welcomed the free Monday move.
That rearranged event came after a revolt at the axing of day three of the showcase and is for for the clans who have stalls at the main weekend event.
Concerns were raised after it was cut from three days to two amid worries over ticket sales .
Dougie MacLean, Karine Polwart and Rachel Sermanni will be among the musicians appearing at the £20-a-ticket June event.
Tens of thousands of spectators are expected to descend on the show which co-incides with Stirling Council's hosting of Armed Forces Day.
The council said the MoD had been called in to help with the traffic logistics of the events.
Fergus Ewing, Tourism Minister, said: "Bannockburn Live is attracting people from across the globe with an affinity to Scotland and given the focus on Scotland's past I am delighted that 39 individual clan organisations are participating in the event."
Mike Cantlay, chairman of VisitScotland said: "On the 700th anniversary of one of the most significant battles in Scotland's history, we had to make sure we created an event to remember - and with such an exceptional amount of activity planned, Bannockburn Live is going to be simply breathtaking."
Pete Irvine, of Unique Events which is staging the event, said: "This mix of the theatre, national and natural history, outdoor activities and top-class music has not been seen before."