Leclerc fastest ahead of Albon in wet final British GP practice
Leclerc, 25, who missed Friday's second practice with an electrical issue, set a best time of one minute 27.419 seconds on soft tyres before the rain started.
Albon, who was third in both Friday sessions, was second fastest - also in the dry conditions and on softs - and 0.173 slower.
The Thai's mechanics were working on the car up to the start of the session to fix an electrical problem.
Aston Martin's Fernando Alonso was third on the timesheets with Pierre Gasly fourth for Alpine and seven times world champion Lewis Hamilton fifth for Mercedes.
Ferrari's Carlos Sainz, last year's race winner, was sixth and U.S. rookie Logan Sargeant seventh for Williams.
Red Bull's double world champion and dominant leader Max Verstappen was only eighth, after dominating Friday, but on the slower medium tyre while Mexican teammate Sergio Perez was 14th.
Verstappen enjoys an 81 point lead in the standings after nine races, all won by Red Bull.
Another win on Sunday would equal McLaren's record run of 11 successive wins from 1988, with Red Bull's sequence starting in Abu Dhabi at the end of last season.
Verstappen has won seven races so far this year and is chasing a sixth successive victory for the first time in his career.
Alfa Romeo's Guanyu Zhou failed to set a time with the mechanics working on a suspected motor generator unit (heat) problem.
McLaren's Lando Norris was under investigation after mechanics left a cooling fan attached to the rear of his car when he left the garage. The Briton stopped at the end of the pitlane for it to be retrieved.