Sebastian Darke top scored for Louth with a superb 70 before being stumped by Richard Bishop off the delivery of Robert Cook, one of his five wickets of the day.
But his side were dismissed for 154 in the 37th over.
Paul Martin (17), Henry Tye (17) and Primosh Perera (13) added support.
In response, Lindum reached the winning total of 156-7 in the 38th over.
Charles Tomlinson top scored with 34 but steady knocks from his colleagues helped the hosts to victory.
Josh Court (3-33) was the pick of the Louth bowlers, aided by Darke (2-48), Perera and Paul Martin, who took a wicket apiece.
On Saturday the Firsts host Grantham (noon), before hosting Bracebridge Heath and Alford in the Winkworth Cup T20 competition on Monday.
The Seconds’ home contest against Barton Town in the Lincolnshire County League First Division fell foul of the conditions, both sides awarded five points.
The Seconds travel to Normanby Park on Saturday (1.30pm).
Louth’s Women’s XI recorded a nine-wicket win over their Alford and District CC counterparts last Wednesday at London Road.
Suzanne Kelleher top scred with 10 for the visitors as they ended their 15 overs on 46-4.
Wickets were taken by Carly Rush (two), Sarah Hunt and Lily Dicker.
Louth reached 47-1 in the ninth over, aided by Dicker (13) and Lydia Norton (12 not out).
Poppy Rowthorn took the wicket of Dicker.
On Sunday the women host Spalding in two contests (11am and 2pm), while the Taverners are at home to Tetford in the East Lindsey League (1.30pm).
Lincs ECB Premier results: Woodhall Spa 161-7 (Caswell 55, Wilson 60), Bracebridge Heath 165-3 (Whapplington 53, Houston 62); Market Deeping 87 (Freeman 5-25), Grantham 88-2;
Louth 154 (Darke 70, Cook 5-31), Lindum 156-7; Boston 167 (Holland 55, Hall 5-44), Sleaford 169-4 (Shorthouse 80); Scunthorpe Town v Alford - abandoned