Tens of thousands of calls for help are being made by children and young people having suicidal thoughts.
Childline said in 2014 it gave just under 17,800 over the phone counselling sessions to children talking about suicide.
The number rose to nearly 19,500 in 2015, and to more than 22,400 in 2016 – an increase of 15% – and the highest level the charity has ever recorded.
The organisation said more than 2,000 had already taken initial steps to taking their own lives, like writing a note, giving away meaningful possessions or planning their death.
Dame Esther Rantzen, who set up Childline in 1986, said due to the volume of calls and messages the charity received some go unanswered.
She said: “Now most children contact us via the internet, they send us emails, they use our online chat service and they use our message board.
“It takes longer to counsel a child online than it does on the phone because it takes longer to type a conversation than it does to speak it.
“We can even now only answer three out of four children who contact us, so we still need more volunteers, we still need to improve the number of children we help.”
Speaking to Sky News, Nikita, 19, said she first rang the helpline when she was 12-years-old after being bullied at school.
She has since rung in at least 15 times and said she struggled with suicidal thoughts throughout her teenage years.
“My best friend moved away at the end of Year 9, then I realised I’m going to have to actually deal with this alone,” she said.
“I was absolutely terrified of going back to school and I did want to take my life because of it, I just felt like I was all alone and like no one really cared about me anymore and I remember being so afraid.”
The NSPCC’s chief executive Peter Wanless said the latest figures are a blunt wake-up call and show there are worrying numbers of children struggling with potentially serious mental health problems.
He said: “We have never seen figures like these before. We hear from more and more children who are just lacking a confidence and a belief in themselves as a result of all sorts of pressures online and offline.
“Young people must know life is worth living and they can lead a life rich in possibilities and happiness.
“When they are suffering from problems it’s vital they get the right help swiftly before these issues snowball into suicidal feelings or even attempts to end their lives.”
:: Anyone feeling emotionally distressed or suicidal can call Childline for help on 0800 1111 or visit childline.org.uk