Hamilton leads Mercedes one-two in final Italian Grand Prix practice
The seven times world champion, who was fastest in Friday's second practice and could take a record sixth win at Monza on Sunday, set a time of one minute 20.117 seconds with Russell 0.093 slower.
Ferrari's Charles Leclerc was third and McLaren's Oscar Piastri fourth.
Red Bull's championship leader Max Verstappen complained of a lack of front grip and lapped only sixth fastest, with his closest rival Lando Norris fifth for McLaren.
Norris, winner in the Netherlands last weekend, is 70 points behind Verstappen with nine races remaining.
Carlos Sainz, on pole at Monza last year, was seventh and the Williams pair of Alex Albon and Franco Colapinto were eighth and ninth with Haas's Nico Hulkenberg completing the top 10.