Graham Clark and Michael Richardson have signed contract extensions, which will keep the pair at Emirates Riverside until the end of the 2019 season.
Clark emerged as one of Durham’s standout players during the 2017 campaign.
After he reached his maiden ton against Glamorgan at the Emirates Riverside in June, he went on to notch nine more half-centuries across all formats.
The 24-year-old went on to finish as the club’s third highest first-class run scorer in the Championship, averaging 36.61.
Richardson, 31, will move into his eighth year at Durham next season after making his first-class debut at Chester-le-Street in 2010.
The South African-born wicket-keeper and top order batsman made nine half-centuries during the 2017 campaign and averaged 30.66 in the Specsavers County Championship.
He also struck his maiden List ‘A’ century earlier this year against Yorkshire at Headingley.
Head Coach Jon Lewis said: “I’m very happy both players have signed fresh terms as they will each have a big role to play as we look to compete for the promotion spots next season.
“Both have a good range of skills that can be utilised in red ball and white ball and in 2018 they have a chance to show what they can do as key members of the first team.”