Model
Marathon M4-100BLS
Rank #12 means 11 of the 1,000 refrigerator models we track cost less to run each year; the 72nd efficiency percentile means it uses less energy for its size than 72% of those models.
What does the Marathon M4-100BLS cost to run per year?
Do the math and the Marathon M4-100BLS's $25/yr running cost puts it at rank #12 of 1,000, among the least expensive refrigerator models we track to keep running. It uses 32% less energy than the U.S. federal standard model in its class, which would cost about $37/yr to run, a saving of roughly $12 a year. Capacity-normalized, it ranks ahead of 72% of refrigerator models we track, a reasonably strong result for the class. Its listing marks it counter-depth, meaning it sits nearly flush with surrounding cabinets rather than protruding a few extra inches like a standard-depth model; that shallower body usually means less interior volume for the same footprint.
Immediately around it on the leaderboard, the Marvel MP*D#24-*G#1A at $24/yr runs a little cheaper and the Marathon M4-150SS at $25/yr runs a little more, a sense of how tightly models are packed at this point in the ranking. A refrigerator typically stays in service for somewhere around 12 years; over that span, the Marathon M4-100BLS's $25/yr adds up to roughly $300 in electricity alone, before purchase price or repairs.
Also sold as: Marathon M4-150SS.
By the numbers
The Marathon M4-100BLS normalized against its whole class, so each figure means something.
What it costs you over time
Running cost is an every-year number, so it compounds. At $25/yr, here is what the Marathon M4-100BLS adds up to before purchase price, water, or repairs enter the math.
Left running for a decade at today's US average rate, the Marathon M4-100BLS costs about $250. That is roughly $120 less than a standard model in its class, which would run closer to $370 over the same ten years.
How the Marathon M4-100BLS compares
The refrigerator class we track runs from $8 to $149 a year. At $25/yr, it runs about $39 a year cheaper than the class median of $64, and it is about $17 a year more than the cheapest refrigerator to run at $8. Against the US federal standard model for its class at about $37/yr, the Marathon M4-100BLS uses 32% less energy.
What drives its running cost
At 5.3 cu ft, the Marathon M4-100BLS is a mid-size refrigerator for its class, which spans 1.2 to 31.7 cu ft with a median of 12.6 cu ft, putting it squarely in the middle of the class on the size lever that drives most of the cost.
- Counter depth vs standard depth. Standard-depth models generally offer more interior volume per unit of width than counter-depth models, a tradeoff between built-in looks and cubic feet.
- Interior volume. More cubic feet of cold air to maintain generally means a bigger compressor and a higher running-cost figure, even among efficient models.
- Compressor technology. How a compressor cycles, full on/off versus a variable-speed inverter design, is one of the biggest hidden differences behind two fridges with similar cubic feet but different running costs.
- Placement and ventilation. Ventilation clearance around the back and top matters more than most owners expect; a fridge starved of airflow runs its compressor longer to hold the same temperature.
Common questions
Is the Marathon M4-100BLS cheap to run?
Yes. Its $25/yr running cost puts it at rank #12 of 1,000, below what most refrigerator models we track cost to run.
How much does the Marathon M4-100BLS cost per month?
About $2.07 a month, which is the $25 annual estimate spread across twelve months at the US average rate of $0.1856/kWh. Your own bill scales with your local electricity rate and how heavily you use it.
How is this running-cost figure calculated?
The formula is annual kWh times price per kWh: 134 kWh from ENERGY STAR times the US average of $0.1856/kWh comes to about $25 a year. It covers electricity only, not the purchase price, water, or installation.
How efficient is the Marathon M4-100BLS for its size?
72nd percentile once size is factored in. That means its size-adjusted efficiency is a real factor in the running-cost figure above; its capacity plays a large role too.
Cheaper to run in the same class
| Rank | Model | Cost/yr |
|---|---|---|
| 10 | Marvel MP*D#24-*G#1A4.9 cu ft | $24 |
| 9 | Dometic C60SBI CARE1.7 cu ft | $23 |
| 8 | Midea MRW14B2ABB1.5 cu ft | $22 |
| 7 | Monogram ZIW241NBW****13.4 cu ft | $22 |
| 6 | Liebherr W525013.1 cu ft | $21 |
Source
ES_1137295_M4-100BLS_10032025120439_80246085View certified refrigerator listingsENERGY STAR data as of July 2026Marathon and M4-100BLS are used here for identification only and are not endorsements. Figures are computed by WattWise Labs from public ENERGY STAR data, not measured in our own lab.