NASA's very first manned mission used silver suits, but no one was exploring the vacuum of space then.
Spacesuits have to be highly reflective and the best color for that isn't silver, it's white.
NASA astronauts wear white suits, since white is the color that reflects the most sunlight in space.
White also protects them from cancer-causing solar radiation, reports Business Insider.
Other space agencies, like in Russia and China, use white for the same reason.
When they first launch though, astronauts wear orange instead, since the bright color.
It makes it easier for them to be spotted and rescued in an emergency.