Mulgrave will play in the Beckett League Premier Division next season after securing yet another promotion.
The Division A leaders confirmed their place in the top flight for 2015 after a crushing 117-run victory at Wykeham on Saturday.
Mario Spagnuolo top-scored with 40 as the pace-setters made 160 before they bowled their hosts out for just 43, Craig Thompson leading the way with four wickets.
Skipper Simon Kipling said he was delighted that his side had realised their ambition to clinch promotion at the first attempt.
“Our aim at the start of the season was to go up, and we’re really pleased to have done it,” he added.
“There is still a lot to play for, however, and we want to make sure that we finish top of the table.”
Mulgrave were promoted from the Derwent Valley League in 2013 and last year they were Beckett League Division B champions, wining the title by a massive 65 points and losing just two games all season.
With just three league fixtures left to play in 2015, the Lythe-based club currently sit top of the Division A standings, 17 points ahead of second-placed Seamer.
The top two meet on August 22 in a face-off that is likely to decide who will finish the season as champions.