Newport claimed the Welsh Premier crown with a comprehensive 43-7 win over Caerphilly at Rodney Parade.
Newport celebrate winning the Welsh Premier two weeks early
With Neath surprisingly losing at home to Cardiff, Newport ran in seven tries to go an unassailable nine points clear with just two games remaining.
"I'm so pleased for the supporters we could finish it at home, it's the icing on the cake," Newport coach Leigh Jones said.
"We've done it through hard work and a good group of youngsters."
Craig Richards found space out wide for the first try, converted by fly-half Dan Griffiths, and the pair produced the same result soon after to make it 14-0 at the break.
No 8 Rhys Jones stretched Newport's lead soon after the restart, with Sam Waldron, Owen Jones, Scott Williams and Chris Thomas also crossing - Ian Carter claiming Caerphilly's consolation try.
"I'm absolutely delighted for myself, but at times like this coaches get too many plaudits and when things are going badly they get too much criticism," Jones added.
"It's about the players, backroom staff, office staff, groundstaff and supporters, not the coach."
The relegation issue remains muddled, as there is still some doubt whether any club will be demoted as the Premiership could be expanded.
Llanelli are bottom with 26 points, two points behind Pontypool who lost at home to Newbridge on Saturday.