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Two sheets, one bench · Compact Cars

M3 Competition Sedan vs GLI

BMW M3 Competition Sedan against Volkswagen GLI, two test sheets laid side by side.

BMW M3 Competition Sedan

19
MPG · $2526/yr
vs

Volkswagen GLI

29
MPG · $1655/yr
More efficient

The gap, in fuel

$871a year between them

The Volkswagen GLI is more efficient — 29 MPG against 19 for the BMW M3 Competition Sedan. Over 15,000 miles a year at $3.20 a gallon that is a saving of about $871 a year, or $4356 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

BMW M3 Competition SedanVolkswagen GLI
Combined economy 19 29
Best year on record 19 30
Worst year on record 19 28
Average across all years 19 29.4
Fuel per year 2526 1655
Gallons per year 789 517
CO₂ g/mi 470 307
Model years tracked 6 6
ClassCompact CarsCompact Cars
Years2022–20272022–2027

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 BMW M3 Competition Sedan or the Volkswagen GLI?

The Volkswagen GLI is more efficient — 29 MPG against 19 for the BMW M3 Competition Sedan. Over 15,000 miles a year at $3.20 a gallon that is a saving of about $871 a year, or $4356 over five years.

Which is cheaper to run, the BMW M3 Competition Sedan or the Volkswagen GLI?

On fuel alone, the Volkswagen GLI: $1655 a year against $2526 for the BMW M3 Competition Sedan, 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 $4356. 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.