- The planet Mercury has no moons.
- The planet Venus has no moons.
- The planet Earth has one moon, as well as four known quasi-satellites, the most famous of which is named Cruithne.
- The planet Mars has two moons.
- The planet Jupiter has 63 confirmed moons, the most discovered of any planet.
- The planet Saturn has 61 confirmed moons.
- The planet Uranus has 27 known moons.
- The planet Neptune has 13 known moons.
- The planet Pluto has 3 known moons.
Therefore, the planets with fewer than four moons are: Mercury, Venus, Earth, Mars, and Pluto.
