diff --git a/src/bench/prevector.cpp b/src/bench/prevector.cpp
index 9b83c42693fd3..adc3d18de000c 100644
--- a/src/bench/prevector.cpp
+++ b/src/bench/prevector.cpp
@@ -87,6 +87,7 @@ static void PrevectorFillVectorDirect(benchmark::Bench& bench)
 {
     bench.run([&] {
         std::vector<prevector<28, T>> vec;
+        vec.reserve(260);
         for (size_t i = 0; i < 260; ++i) {
             vec.emplace_back();
         }
@@ -99,6 +100,7 @@ static void PrevectorFillVectorIndirect(benchmark::Bench& bench)
 {
     bench.run([&] {
         std::vector<prevector<28, T>> vec;
+        vec.reserve(260);
         for (size_t i = 0; i < 260; ++i) {
             // force allocation
             vec.emplace_back(29, T{});