- 2025–2027 Factory-verified
O on all trims; fleet plan; the 2025 guide names it OnStar One Business Plus
R8G Factory-verified
Also described as OnStar One Fleet, 12 months of service
Also documented for CadillacChevroletGMC
Documented applications
- 2025–2027 Factory-verified
Preferred, Sport Touring, Avenir: O; the 2025 guide names the plan OnStar One Business Plus
- 2025–2027 Factory-verified
2027: all trims: O; the 2025 list reads OnStar One Business Plus - 12 Months of Service; the 2026–2027 lists name the plan differently
- 2025–2026 Factory-verified
all trims: O; the 2025 list calls it OnStar One Business Plus, 12 months of service
This page aggregates every documented appearance of R8G in the Buick reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.