The midfielder is a hugely important cog in Marcelo Bielsa's precisely tuned machine, and his credentials as a fan favourite are only enhanced by the fact that he is a homegrown talent.
So far this season, Leeds have lost six of the eight Premier League matches that he has missed out on, and he recently passed 200 career appearances at Elland Road.
It’s little wonder, therefore, that he is valued so highly, and former Scotland manager Alex McLeish has argued that his monetary worth to the Whites is immense too.
Speaking to Football Insider, he said: “Kalvin Phillips would command a monster fee.
“Homegrown guys tend to be much more expensive. When you’re maybe casting your eyes abroad and you’re looking, you could possibly get a wee bargain here and there.
“But when you get home-grown guys like Phillips, tying him down is of the utmost importance.
“I think there’s a few clubs that could be definitely looking at a homegrown guy.”
Phillips’ current deal at Elland Road expires in 2024, and the Whites have resisted big interest in him before, with Aston Villa launching a bid to sign the 25-year-old in 2019.
Elsewhere, Football League World are reporting that Leeds are interested in signing Barnsley midfielder Callum Styles.
The 21-year-old, is capable of operating in the centre of the park or on the left flank, and has established himself as a key figure in the Tykes’ unexpected promotion push this season, featuring 36 times in the Championship.
The youngster has been in impressive form at Oakwell this term, and was named as the EFL’s Young Player of the Month for February.
Whether or not Leeds make a move may ultimately hinge on if Barnsley are able to secure promotion to the Premier League.
The Tykes are currently fifth in the Championship table with seven games left to play.
As well as Leeds, Southampton and Norwich City are both said to be keen on a potential summer raid for Styles.
We’ve gathered the best of the rest of today's Premier League transfer speculation below:
1. Leeds want Styles
Leeds United want to sign Barnsley talent Callum Styles in the upcoming summer transfer window. (Football League World) (Photo by Alex Pantling/Getty Images) Photo: Alex Pantling
2. Berge future discussed
Former Norway international Erik Thorstvedt believes a move to Aston Villa or West Ham would be the “natural next step” for Sheffield United ace Sander Berge. (Nettavissen) (Photo by OLI SCARFF/POOL/AFP via Getty Images) Photo: OLI SCARFF
3. Bull urges Blades to ignore Terry
Wolves legend Steve Bull doesn’t believe John Terry is the right man for the vacant Sheffield United job. (Football Fancast) (Photo by Nick Potts - Pool/Getty Images) Photo: Pool
4. Hendrie wants Wilson at Villa
Former Aston Villa midfielder Lee Hendrie has urged his old side to consider the possibility of signing Callum Wilson if Newcastle United go down. (Transfer Tavern) (Photo by Stu Forster/Getty Images) Photo: Stu Forster
5. Bruce eager to keep Murphy
Newcastle United boss Steve Bruce has hopes the Magpies are able to tie down Jacob Murphy down on fresh terms at the club, with his current deal set to expire in the summer. (Various) (Photo by PETER POWELL/POOL/AFP via Getty Images) Photo: PETER POWELL
6. Burnley keen on Twine
Burnley and Queens Park Rangers are among clubs interested in signing Swindon Town star Scott Twine on a free transfer in the summer transfer window. (The Sun) (Photo by Stu Forster/Getty Images) Photo: Stu Forster