Derby rivals Sunderland's 3-0 home victory over Everton on Wednesday evening consigned their neighbours to the Sky Bet Championship once again along with Norwich and Aston Villa, casting doubt on the future of manager Rafael Benitez, who has a release clause in the contract he signed in March.
In a statement directed at the club's fans, Charnley said: "Tonight we are devastated at our relegation from the Premier League, as I know every single person connected to this football club will be.
"I want to thank all of the fans for the support you have shown for the club you love throughout the season, in spite of this massive disappointment and under-achievement.
"Your support throughout has been magnificent, but I want to pay particular thanks for the incredible backing you have given to Rafa and the team during the latter part of the season. Nothing more could be asked of you and I am truly sorry we have not given you the outcome you deserve.
"I also want to thank every single member of staff here. This club is their livelihood, but they are fans too. To go through the threat of relegation last season and then to suffer a worse fate this time around has been very hard for them.
"I know that each and every one of them has done whatever they could to help us out of the situation we now find ourselves in.
Barclays Prem
1 Leicester 80
2 Tottenham 70
3 Arsenal 68
4 Man City 65
5 Man Utd 63
6 West Ham 62
7 So'ton 60
8 Liverpool 59
9 Chelsea 49
10 Stoke 48
11 Swansea 46
12 Everton 44
13 Watford 44
14 C Palace 42
15 W Brom 42
16 B'mouth 42
17 S'land 38
18 Newcastle 34
19 Norwich 34
20 A Villa 17
"We know that supporters want to know what the future holds and will want to hear more from us as soon as possible. The process of scrutinising what went wrong and planning for what is to come has already begun.
"Right now, of course, Rafa and the team must prepare for the final game of the season but after that, please rest assured we will communicate more fully with supporters."
Positive noises have emerged from the Benitez camp in recent days suggesting the Spaniard could remain on Tyneside in the wake of relegation, and although he will escape the wrath of supporters at Sunday's final day clash with Tottenham after more than making a fist of dragging the club out of trouble, there is work to be done to present him with an attractive proposition.
Owner Mike Ashley abandoned his recruitment model and sanctioned transfer spending in excess of £80million during an ill-starred campaign, but his money was in too many cases badly spent and with head coach Steve McClaren failing to mobilise a squad ill-suited to the job at hand, the club was on a slippery slope long before Benitez was handed his firefighting role.
The loss of a share of the new riches on offer in the Premier League from next season will come as a huge blow to a business which prides itself on turning a profit, and serious questions need to be asked and answered as they look for a way forward.
Former defender Warren Barton put the blame squarely at the feet of the players.
He told Sky Sports News: "It wasn't just this season, it started happening a couple of years ago with the players coming in. Andros Townsend looks a good player but other than him, I don't think there's anyone else, for me, to still be at the club.
"They won't care, they get in their cars and drive off. You can tell by the body language throughout the season.
"I hope Rafa stays, but if he doesn't it tells you a bit about him as well. It's time to clear the decks, regroup, refocus and go forward because we need to bounce back straight away."
The Canaries were condemned to the drop despite a 4-2 victory over Watford.