This is a chart created by Penn State University. It matches most pumping schedules found online.
The EPA recommends pumping your septic tank every 3 to 5 years.
Tank Size (gal)
Household Size (number of persons living in the household)
1 2 3 4 5 6 7 8
500* 5.8 2.6 1.5 1.0 0.7 0.4 0.3 0.2
750* 9.1 4.2 2.6 1.8 1.3 1.0 0.7 0.6
900 11.0 5.2 3.3 2.3 1.7 1.3 1.0 0.8
1000 12.4 5.9 3.7 2.6 2.0 1.5 1.2 1.0
1250 15.6 7.5 4.8 3.4 2.6 2.0 1.7 1.4
1500 18.9 9.1 5.9 4.2 3.3 2.6 2.1 1.8
1750 22.1 10.7 6.9 5.0 3.9 3.1 2.6 2.2
2000 25.4 12.4 8.0 5.9 4.5 3.7 3.1 2.6
2250 28.6 14.0 9.1 6.7 5.2 4.2 3.5 3.0
2500 31.9 15.6 10.2 7.5 5.9 4.8 4.0 3.5
Years between pumping