Watch: King Charles shares message during NTAs to celebrate Emmerdale's 50th anniversary
The ITV soap is celebrating the milestone this year and was also a big winner at the awards, scooping the coveted serial drama gong.
And the night was even more special when His Majesty's pre-recorded speech was played.
The monarch, 73, said he was "delighted" to be celebrating the soap and joked that he was "so old" that he could remember when it was called Emmerdale Farm.
"It is a testament to all the hard work of its production team that it has since become such an important British institution and a major British export with hundreds of thousands of fans from Scandinavia to New Zealand, all keen to follow the fortunes of what is left of the Sugdens and their new neighbours," he said.
“What makes Emmerdale so special is that it has kept true to the vision of its original writer, Kevin Laffan, who wanted to demonstrate that farming is not just a job, it’s a whole way of life.
“On a daily basis, Emmerdale continues to depict what life is really like for those who work the land and protect our precious countryside.
"It also stresses brilliantly something that concerns me greatly: the long-term sustainability of the way we produce our food."
The King said he was also "heartened" by the production team’s efforts off screen.
"Their ambition to achieve net-zero emissions by 2030 has already made Emmerdale one of the first British programmes to be awarded Albert certification, recognising its efforts to reduce the environmental impact of its production process and to create content that stresses the importance of establishing a sustainable future," he said.
“So it is only right that the National Television Awards acknowledge the enormous contribution Emmerdale has made and I hope those watching will join me in sending a warmest congratulations on its 50th anniversary.
"And wishing it an equally successful future.”
Sharing a photo of the moment on Instagram, the soap said: "Well that was a birthday surprise for all of us at Emmerdale at the @officialntas!
"We're over the moon ... thank you so much Your Majesty for taking time out earlier this year to send us your wonderful wishes."
NTA's executive producer Kim Turberville, said: “We were delighted to be able to surprise the Emmerdale team with such an important message. Fifty years of iconic television out of the North is a huge achievement and rightly deserves to be celebrated in the best way possible.
"It is with great thanks to His Royal Highness for delivering this message to pop the icing on their birthday cake ahead of their very special weekend."