Pollock's first half double and clinching third after the break accounted for Leamington at the Jakemans Community Stadium.
His goals in the 28th, 40th and 51st minutes completed United's first hat-trick on home soil since Dayle Southwell in February 2015.
United were already on the front foot by the time their first goal arrived - with Jordon Crawford particularly prominent. He forced Callum Hawkins into an excellent sixth minute save following Jake Wright's cushioned header into his path.
Crawford dragged an effort across goal and wide after Ben Pollock had nodded down Sam McLintock's cross - and then headed over from a Keenan Ferguson delivery.
United's breakthrough arrived when POLLOCK intercepted Theo Streete's short backpass before rounding Hawkins to slot home.
Leamington threatened a reply, with Ben Pollock blocking superbly to deny Dan Turner, with Jack Edwards heading the resulting Devon Kelly-Evans corner narrowly wide.
Wright was denied by a fine Hawkins stop - but POLLOCK swooped five minutes before the break to roll home the rebound.
POLLOCK grabbed the matchball six minutes after half-time after Crawford had done all the hard work on the left to tee up his free-scoring team-mate.
Pollock sailed another effort narrowly wide in the 66th minute - as the Pilgrims remained in full control.
There was a late cameo from the bench for striker Jordan Burrow, who made his return eight months after his last appearance at Chorley.
Boston (3-4-1-2): Sam Long; Jo Cummings (Lebrun Mbeka 63), Shaun Pearson, Ben Pollock; Keenan Ferguson, Tom Platt, Sam McLintock, Alex Brown; Scott Pollock (Jordan Burrow 81); Jake Wright (Will Atkinson 70), Jordon Crawford. Subs (not used): Tom Solanke, Rhys Davies (gk).
Leamington (4-2-3-1): Callum Hawkins; Dan Meredith, Theo Streete, Jack Lane, Louis Hall; Simeon Maye (Junior English 73), Adam Walker; Charlie Williams, Jack Edwards (Liam Cross 63), Devon Kelly-Evans; Dan Turner (Rackeem Reid 63). Subs (not used): Connor Taylor, Jack Sang.
Referee: Abigail Byrne.
Attendance: 1,219 (19 visitors).
PIC: Tim Hoff.