School bus endorsement (S)
S is the most gated endorsement on the list, and not because the test is hard. It stacks on top of P, adds a skills test in an actual bus, and then every state layers its own background and certification requirements on top of the federal ones.
- Code
- S
- Test
- Knowledge test and skills test
- Prerequisite
- Passenger (P) endorsement
- Background check
- State-level, varies — often extensive
- Typical state fee
- Usually under $25, plus state certification costs
Ready to check yourself? Take the free School bus (S) practice test — no sign-up.
P first, then S
The school bus endorsement is not standalone. Federal rules require the passenger endorsement as a prerequisite, so drivers go through P — knowledge test plus a skills test in a passenger vehicle of the right class — before S is even on the table.
That ordering surprises people who assume a school bus is simply a category of bus. In licensing terms it is a passenger vehicle first and a school bus second, and the endorsements reflect that.
What the tests cover
The S knowledge test is dominated by the loading and unloading zone, because that is where the fatalities happen. Expect detailed questions on the danger zone around the bus, the mirror-check sequence, and the specific procedure for a student who drops something near the wheels.
The skills test is done in a school bus and adds a pre-trip inspection with bus-specific items — emergency exits, the stop arm, crossing gate, mirrors and the student-check sweep at the end of a route.
- The danger zone and where students disappear from view
- Loading and unloading procedure, including the escort signal
- Railroad crossing procedure for buses
- Emergency exits and evacuation types
- The post-route sweep for sleeping students
What the state adds on top
The federal endorsement is the floor, not the ceiling. States commonly add their own school-bus driver certification, a fingerprint-based criminal background check, a physical or drug screen beyond the DOT physical, and periodic refresher training.
Because those requirements are set locally and change, treat your state education or licensing agency as the authority for the full list. This page covers what the endorsement itself requires; the certification around it is state business.
Frequently asked
- Do I need a passenger endorsement to get a school bus endorsement?
- Yes. P is a federal prerequisite for S, and it carries its own knowledge and skills tests.
- Is there a skills test for the school bus endorsement?
- Yes, and it has to be taken in a school bus. That makes S one of only two endorsements with a behind-the-wheel component, alongside P.
- What class of CDL do I need to drive a school bus?
- It depends on the bus. A full-size bus over 26,001 lbs is Class B territory; a smaller bus carrying 16 or more people including the driver can fall under Class C. The S endorsement sits on whichever class fits the vehicle.
- How long does the school bus endorsement take to get?
- Longer than the knowledge-only endorsements. Between the P prerequisite, scheduling a skills test in a bus, and state certification and background checks, several weeks is a realistic expectation.