Surrey captain Gareth Batty and batsman Arun Harinath have signed new two-year deals, which will keep the pair at The Oval until the end of the 2018 season.
Spinner Batty, who turns 39 next week, took 41 wickets at an average of 31.21 in the County Championship this year.
His form led to a recall to the England Test squad for the two-match series in Bangladesh later this month.
Left-hander Harinath, 29, scored 707 runs at an average of 35.35 in 11 Championship appearances in 2016.
Batty has also been granted a testimonial year by Surrey in 2017.