Townsend said: "I'd like to thank these players for the work-rate and commitment they've shown as part of our preparations for the Rugby World Cup in Japan.
"They've been a credit to a very strong group of players, and we wish them all the best in the season ahead."
He added: "Players are often called up from beyond the 31-man group that travels to a world cup, so I'd encourage these players to keep working as hard on their skills and fitness as they have over the summer, as we may need to call on them in the weeks ahead."
The national team's preparations for Japan will intensify once again next week as a series of four home-and-away Summer Test matches begins when Scotland travel to face France on Saturday 17 August, before hosting the return fixture at BT Murrayfield a week later (Saturday 24 August).
The first leg of the double header against Georgia follows on Saturday 31 August, where Scotland will be the first Tier 1 nation to face the Lelos on home soil at the Dinamo Arena in Tbilisi.
The national team will then complete its competitive preparations for RWC2019 on home soil, when they face Georgia on Friday 6 September at BT Murrayfield.