275 gallon vertical oil tank chart
The 275 vertical is the standard home heating oil tank: 27″ wide, 44″ tall, 60″ long, standing on end so the oval faces you. Dip a clean stick to the bottom through the fill or gauge opening, read the wet line in inches, and convert below.
gallons % of a full 275 gallon vertical tank
Enter a reading to convert it, fill the tank pictures, and highlight your row in the chart below.
| Inches | Gallons | Inches | Gallons |
|---|---|---|---|
| 1″ | 2 | 23″ | 144 |
| 2″ | 5 | 24″ | 151 |
| 3″ | 9 | 25″ | 158 |
| 4″ | 14 | 26″ | 166 |
| 5″ | 19 | 27″ | 173 |
| 6″ | 25 | 28″ | 180 |
| 7″ | 31 | 29″ | 187 |
| 8″ | 38 | 30″ | 194 |
| 9″ | 44 | 31″ | 201 |
| 10″ | 51 | 32″ | 209 |
| 11″ | 58 | 33″ | 216 |
| 12″ | 65 | 34″ | 223 |
| 13″ | 72 | 35″ | 229 |
| 14″ | 80 | 36″ | 236 |
| 15″ | 87 | 37″ | 243 |
| 16″ | 94 | 38″ | 249 |
| 17″ | 101 | 39″ | 254 |
| 18″ | 108 | 40″ | 260 |
| 19″ | 115 | 41″ | 265 |
| 20″ | 123 | 42″ | 269 |
| 21″ | 130 | 43″ | 272 |
| 22″ | 137 | 44″ | 274 |
Generated 2026-06-12. Computed from nominal tank geometry at 231 cubic inches per gallon, with a 2.2 percent dished-head allowance calibrated to the manufacturer’s published capacity chart. Matches the chart books oil dealers use within about a gallon.
Reading the numbers
- Full is about 274 gallons. A normal fill stops a few inches short of that, so a "full" tank is typically 240 to 250 gallons of oil.
- The middle of the tank moves about 7.2 gallons per inch. The top and bottom curves hold less per inch, which is why the chart is not a straight line.
- A quarter tank (about 69 gallons) sits at 13 inches on the stick. That is a sensible reorder point in winter.
- Below 10 inches (about 51 gallons), schedule a delivery now. A cold snap can burn 7 or more gallons a day, and the sludge that settles near the bottom of older tanks can clog your filter before the tank actually runs dry.
Common questions
Why does my 275 gallon tank only take 240 gallons?
Three reasons: the tank really holds about 274 gallons with its dished heads counted, the delivery whistle stops the fill a few inches below the top to leave an air gap, and a little oil sits below the outlet. A 230 to 250 gallon fill into an empty 275 is normal. More detail in why a 275 holds about 240.
How many gallons is one inch of oil?
In the straight middle section of a 275 vertical, about 7 gallons per inch. In the rounded bottom and top sections it is less, which is why you should use the chart rather than multiplying.
Is the float gauge accurate?
Float gauges drift and stick, and the marks are coarse. Treat the gauge as a trend indicator and the stick as the truth. See reading an oil tank gauge.
Is my tank vertical or horizontal?
Look at the oval end. If the oval stands taller than it is wide (44″ tall, 27″ wide), it is vertical and this chart applies. If it lies wider than tall, use the 275 horizontal chart.
Related
- 330 gallon vertical chart (same shape, 12 inches longer)
- How to stick an oil tank
- How long will my oil last?