The pair, described by award host, Dermot O'Leary as "a British institution loved by one and all", also received a tribute from the Prince of Wales.
This Morning presenter, Phillip Schofield read a letter from the Prince who said: "The warmth and empathy they show towards charitable causes, their viewers and their deep friendship towards one another are as great achievements as their countless and well-deserved awards. The nation has taken them to their hearts."
The audience were shown a video tribute with appearances from their mothers, former Newcastle United striker Alan Shearer, Robbie Williams and Simon Cowell.
The pair were both clearly taken with the accolade with Ant struggling to contain his emotions on the stage.
Accepting the special award, Dec thanked Ant saying: "Neither of us would be here if it wasn't for each other."
Earlier in the night the duo celebrated winning the Best Entertainment Award, it was the 13th consecutive time the pair had lifted the honour.
Another big winner on the night was Coronation Street who won the Best Serial Drama and actress, Julie Hesmondhalgh won the Serial Performance Award.
She won the award for her heart-wrenching performance in the controversial right-to-die storyline which ended with the suicide of her on-screen character, Hayley Cropper, on Monday.
Among the other actors she beat to the prize was David Neilson who plays her on-screen husband Roy.
Accepting her award with Neilson by her side, she told the audience: "We said that if either of us were lucky enough to get this tonight we'd come up together because there ain't no Hayley without Roy and there ain't no Roy without Hayley."
The climax of the plot pulled in millions more viewers and prompted an increase in calls to The Samaritans.
A peak audience of 10.6 million viewers saw Hayley take an overdose after giving up her struggle with incurable cancer - two million more than the corresponding episode the week before.
Other NTA winners included I'm A Celebrity... Get Me Out Of Here! which won the Entertainment Award and This Morning, which won the Daytime Award.
Paul O'Grady also won the Factual Entertainment for his show, For the Love of Dogs.
Strictly Come Dancing won the Talent Show Award, with stars of the ballroom show, including winner Abbey Clancy and host Tess Daly, accepting the night.
Educating Yorkshire was a popular winner on the night, as the teachers and pupils featured in the programme picked up the Best Documentary Award.
Best TV Dectective was a new addition to the awards list this year and Hollywood actor Kiefer Suterand arrived to present the prize to Benedict Cumberbatch for his role in Sherlock.
Current X Factor champion Sam Bailey opened the show alongside U.S singer Michael Bolton and the Thornhill Community Academy choir.