Top scorer Finlay Sinclair-Smith put the Merseysiders in front with a first half penalty and they doubled their lead through Jack Bainbridge on 68 minutes.
Kane Drummond gave Macclesfield hope 12 minutes from time, but the pre-match favourites will remain in the NPL for the 2024/25 season.
It is another momentous occasion for Marine to celebrate, some three years after their famous FA Cup run where they faced Tottenham Hotspur in the third round.
They were only promoted back to the NPL Premier Division two years ago, after beating Runcorn in the West Division play-off final, in the same season they also won the Liverpool Senior Cup.
It’s their reward for sticking with manager Neil Young, despite being relegated from the NPL top division after 40 consecutive seasons back in 2019, and they have now reached National League North for the first time.
Marine will join Radcliffe in moving up to Step 2 next season.
Photo: Sean Walsh
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