2018 Cadillac CT6 EPA Fuel Economy Summary

The 2018 Cadillac CT6 delivers an EPA-certified 21–25 MPG combined (18–22 city / 26–30 highway depending on engine and drivetrain) across 4 configurations. Plug-in hybrid (PHEV) models offer up to 31 miles of all-electric range at 62 MPGe. Estimated annual fuel costs range from $2,950 to $3,600.

Combined MPG
21–25 MPG
55% city / 45% highway weighted
City MPG
18–22 MPG
Stop-and-go urban cycle
Highway MPG
26–30 MPG
Sustained open-highway test
Annual Fuel Cost
$2,950–3,600
EPA estimate @ 15,000 miles/yr

2018 Cadillac CT6 Powertrain & Efficiency Comparison

Factual efficiency differences across gasoline, hybrid, plug-in hybrid, and electric variants

Internal Combustion

Standard Gasoline Trims

21–25 MPG Combined

Annual Fuel Cost: $2,950–$3,600 (3 configurations)

Plug-In Hybrid

Plug-In Hybrid (PHEV)

31 mi EV Range • 62 MPGe

Gasoline Combined: 25 MPG • Annual Energy Cost: $3,050

Official EPA Fuel Economy Ratings by Configuration (4 Variants)

Laboratory certification test values across engine, transmission, and drivetrain permutations

Configuration / Model Powertrain Drivetrain Transmission City Highway Combined EV Range Annual Fuel Cost CO2 (g/mi)
CT6 Premium 2L 4-Cyl Gas Rear-Wheel Drive Automatic (S8) 22 MPG 30 MPG 25 MPG — $3,050 —
CT6 AWD Premium 3L 6-Cyl Gas All-Wheel Drive Automatic (S8) 18 MPG 26 MPG 21 MPG — $3,600 —
CT6 AWD Regular 3.6L 6-Cyl Gas All-Wheel Drive Automatic (S8) 18 MPG 27 MPG 21 MPG — $2,950 —
CT6 Plug-In Premium and Electricity 2L Plug-in Hybrid Rear-Wheel Drive Automatic (variable gear ratios) 56 MPGe (23 MPG) 71 MPGe (29 MPG) 62 MPGe (25 MPG) 31 mi $3,050 —
EPA Test Methodology: Fuel economy estimates are determined by vehicle manufacturers in accordance with EPA regulations (40 CFR Part 600) and verified by EPA laboratories. Estimates assume 15,000 miles per year of driving (55% city, 45% highway) at prevailing fuel and electricity prices.

Deterministic Fuel Cost & Consumption Benchmarks

Standardized annual energy consumption and operating cost metrics based on 15,000 annual miles

Fuel Cost per 25 Miles

$3.50–$4.17

Based on $3.50 per gallon regular gasoline

Annual Fuel Consumption

600–714 Gallons

Estimated annual energy units needed for 15,000 miles

5-Year Fuel Cost vs Avg Vehicle

Official EPA Benchmark

Compared to the average new vehicle over 5 years

Related Official Reports for 2018 Cadillac CT6

Cross-reference safety ratings, owner defect complaints, and recall campaigns

Official US Government Data Provenance

Fuel economy ratings, electric range figures, and energy cost estimates on this page are retrieved directly from the United States Environmental Protection Agency (EPA) and U.S. Department of Energy (FuelEconomy.gov) certified vehicle database.

Local Production Store Compiled: August 2026 • Deterministic Audited Dataset • Zero Dynamic External API Runtime Latency.