Surviving a draw against South Zone on the last day helped North Zone retain their position on top of the BCL points table.
Asked to follow on after trailing by 259 runs in the first innings, Farhad Hossain and Naeem Islam added 136 runs for the third wicket, as their individual centuries helped North Zone survive the fourth day on 403 for 8.
Farhad's 119 was studded with nine fours and three sixes, while Naeem remained unbeaten on 129, having batted for more than six hours. Naeem is now the second-highest run-getter of the tournament - averaging 106.25 - behind Tushar Imran, whose double-hundred helped South Zone post 501 in 144.4 overs.
Tushar, the No.4 batsman, added 215 runs for the fourth wicket with Shahriar Nafees (74) and later strung a 96-run stand for the sixth wicket with Mosaddek Hossain, who chipped in with a 65-ball 57.
Tushar knocked off 220 runs - his highest first-class score - to improve on his unbeaten 203 in the National Cricket League in 2015.
Suhrawadi Shuvo returned the best figures for North Zone, picking up 4 for 105, before their batting line-up folded for 242 in the 63rd over.
South Zone offspinner Nahidul Islam's successive five-fors in the game earned him his maiden first-class ten-wicket haul and kept his team's pursuit of victory alive till the end. He found able support in Abdur Razzak and Al-Amin Hossain, who claimed five wickets between them, but their efforts proved insufficient as North Zone managed to retain the last two wickets.
Central Zone, meanwhile, registered their first win in the tournament, after crushing East Zone by 227 runs at Khan Shaheb Osman Ali Stadium.
Put in to bat, Central Zone were bowled out for 328 in the first innings, despite fifties from Nurul Hasan (65) and Mohammad Sharif (70). East Zone seamer Abu Jayed picked up 5 for 77, while Saqlain Sajib and off-spinner Afif Hossain took two wickets apiece.
Central Zone later snatched a first-innings lead of 117 runs, as Sharif, Shuvagata Hom and Mosharraf Hossain fetched combined returns of 8 for 143 to skittle East Zone for 211.
Half-centuries from Marshall Ayub and Taibur Rahman then helped Central zone add 282 in their second innings; their overall lead soaring to 399 runs.
With his side chasing 400, East Zone captain Alok Kapali (71) found little support from other batsmen, as Central Zone's bowling attack - led by Hom's four-wicket haul - strangled East Zone to 117 all out in 56.2 overs.
Sharif's all-round performance - 6 for 78 coupled with 71 runs - earned him the Player-of-the-Match award.
South Z (BD) vs North Z (BD)
Cent Z (BD) vs East Z (BD)
Mohammad Isam is ESPNcricinfo's Bangladesh correspondent. @isam84