Good question...well...differentiation, integration (limited to "easy functions" and "easy substitutions"), complex numbers (no exponential form(!) ) and complex loci, conic sections, stats (without any calculus(!) ), trig equations, arithmetic and geometric sums and....that's pretty much it! (If I missed anything it wouldn't be much)
There's no way I can possibly pass STEP if I didn't take that extra university courses basically... That uni course merely brought me on par with you UK maths students

(It's scary to see that some of the "second year uni" stuff here is in the FP2/FP3 syllabus)
Yeah but the "calculus" course is the only core maths course available. The full name is "mathematics with calculus". (The other one is just stats)