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Two sheets, one bench · Large Cars

Phantom vs Maybach S680 4matic

Rolls-Royce Phantom against Mercedes-Benz Maybach S680 4matic, two test sheets laid side by side.

Rolls-Royce Phantom

13
MPG · $3692/yr
vs

Mercedes-Benz Maybach S680 4matic

14
MPG · $3429/yr
More efficient

The gap, in fuel

$264a year between them

The Mercedes-Benz Maybach S680 4matic is more efficient — 14 MPG against 13 for the Rolls-Royce Phantom. Over 15,000 miles a year at $3.20 a gallon that is a saving of about $264 a year, or $1319 over five years.

SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026

How this is worked out

  1. Start from the EPA combined figure for the model year — a laboratory test cycle run to a fixed procedure, not a road result. Where a year sold several engines or drivetrains, the trims are averaged and the trim count is printed beside the row so you can see how much averaging is behind it.
  2. Fix a pump price. This site keeps one reference price, $3.20 a US gallon, fixed JUL 2026 and printed next to every dollar figure it produces. It is an assumption with a date on it, not a quote — put your own price in.
  3. Fix an annual distance. Every annual figure on this site uses 15,000 miles a year, roughly the US average. A cost per year with no stated distance is not a number, it is a mood.
  4. Divide distance by economy for gallons, multiply by price for the year's fuel, divide price by economy for one mile. The per-kilometre line is that last figure divided by 1.609344 — the same money, in the unit most of the world drives in.
  5. Stop there. No depreciation, no tyres, no insurance, no servicing. This is the fuel line of the ledger and it is labelled as one; depreciation usually dwarfs everything on it.
gallons/yr = miles/yr ÷ MPG
fuel  $/yr = gallons/yr × $/gal
cost  $/mi = $/gal ÷ MPG
cost  $/km = cost $/mi ÷ 1.609344

The full method, the licence note, and what a test figure cannot tell you →

Both sheets, line for line

Rolls-Royce PhantomMercedes-Benz Maybach S680 4matic
Combined economy 13 14
Best year on record 14 15
Worst year on record 13 14
Average across all years 13.8 14.7
Fuel per year 3692 3429
Gallons per year 1154 1071
CO₂ g/mi 656 610
Model years tracked 24 6
ClassLarge CarsLarge Cars
Years2004–20272022–2027

Highlighted cells are the better of the two on that measure. Fuel costs at $3.20/gal over 15,000 miles.

SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026

Questions asked across the counter

Which is more fuel efficient, the Rolls-Royce Phantom or the Mercedes-Benz Maybach S680 4matic?

The Mercedes-Benz Maybach S680 4matic is more efficient — 14 MPG against 13 for the Rolls-Royce Phantom. Over 15,000 miles a year at $3.20 a gallon that is a saving of about $264 a year, or $1319 over five years.

Which is cheaper to run, the Rolls-Royce Phantom or the Mercedes-Benz Maybach S680 4matic?

On fuel alone, the Mercedes-Benz Maybach S680 4matic: $3429 a year against $3692 for the Rolls-Royce Phantom, both at $3.20 a gallon over 15,000 miles — an assumption fixed JUL 2026. Fuel is the only line being compared: depreciation, insurance, tyres and servicing are not in it, and they routinely matter more than this gap.

Is the difference big enough to change the decision?

Across five years of that same driving the gap comes to about $1319. That is real money, and it is also roughly what one year of depreciation does to a new car — so treat it as one line in the ledger rather than the whole argument.

Both entries carry the full year-by-year history and the pump-price ledger. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.

See all 10 sites in this family, with what each one answers

Published by

Amit Sharma

Auckland real-estate agent and marketer. Builds free, sourced data tools.