Five-time Burghley winner Andrew Nicholson put a heap of pressure on Price with a clear round on Swallow Springs in their first four star start to finish third on 32.1 with Townend on last year's winner Ballaghmor Class second on 31.9 points.
Big Read: The Prices are alright - sustaining New Zealand's equestrian dynasty
Price was also 10th on Bango on a day in which only eight of the remaining 39 combinations managed to go clear and inside the required time. Price had two of those eight finishes.
The win meant "absolutely everything" to the Rio Olympian.
"I'm just so thrilled."
It is Price's second four-star title, after winning Luhmuhlen aboard Wesko in 2014. Between them the husband-and-wife team have collected four four star crowns.
Tim Price, up to fourth-ranked rider in the world, has been a podium finisher at the Badminton, Burghley, Kentucky and Pau premier events.
In terms of Burghley, Price finished second in 2015, fourth in 2016, and fifth last year so he can scarely be faulted on consistency.
Today was the 14th Burghley crown for a New Zealand rider and 30th overall four star victory, a list headed by the greats Mark Todd and Andrew Nicholson with nine apiece.
"He has always been putting his best hoof forward with everything," Price said.
"I'm really just trying to stay up with the missus," he quipped of his top performing wife.
"She is a great driving force for both of us – we are lucky to have each other. I am sure we will look back on this in years to come – 2018 has been a very special year."
Price had conceded Ringwood Sky Boy wasn't the world's finest showjumper but was "the world's greatest trier".
"Burghley is the place you want to come to and put your best foot forward. You have got to bring your best game – from a riding point of view, this is where you want to be your best.
"This is very special – I will always carry it with me."
Todd added four faults aboard NZB Campino to finish 18th on 49.6, while Caroline Powell, a four star winner aboard Lenamore at Burghley in 2010, was 31st on On the Brash, while Dan Jocelyn was 32nd on Dassett Cool Touch.
Burghley newcomer Ginny Thpmpson withdrew Star Nouveau after the cross country while Nicholson also chose not to bring Jet Set IV back for the showjumping and Todd was eliminated during Sunday morning's cross country aboard Kiltubrid Rhapsody.
The Prices aren't finished for the year either. Both are in New Zealand's eventing team for the world games in North Carolina this month, along with Todd, Jocelyn and veteran Blyth Tait.
