The stomach sits in the left upper quadrant (LUQ) of the abdomen, just below the diaphragm and slightly left of the body’s midline. Most of the organ tucks under the lower ribs on your left side, partly hidden beneath the liver.
The Four-Quadrant System
Doctors divide the abdomen into four quadrants using two imaginary lines: one running vertically through the belly button and one running horizontally across it. The stomach falls into the left upper quadrant, sharing that space with the spleen, the tail of the pancreas, part of the colon, a portion of the small intestine, and the left kidney. Although the bulk of the stomach sits left of center, a small portion of it crosses the midline and extends into the right upper quadrant, overlapping with the liver.
The Nine-Region System
A more detailed map splits the abdomen into nine regions using four lines instead of two. Under this system, the stomach spans several zones. The main body of the stomach occupies the left hypochondriac region, which sits beneath the left ribcage. The central upper portion of the stomach, where it connects to the esophagus and curves toward the right, lies in the epigastric region, the area just below the breastbone. Parts of the stomach can also dip into the umbilical region (around the belly button) when the stomach is full and expanded.
What Surrounds the Stomach
The stomach doesn’t float freely. It’s anchored to several neighboring structures. Directly above it sits the diaphragm, the dome-shaped muscle you use to breathe. The liver drapes over the stomach’s upper right portion, which is why the two organs overlap when viewed from the front. To the left and slightly behind, the spleen sits close enough that a severe blow to the left side can injure both organs. The pancreas lies behind and below the stomach, running horizontally across the back wall of the abdomen. A sheet of fatty tissue called the greater omentum connects the stomach’s lower curve to the transverse colon, spleen, and diaphragm, helping hold everything in place.
Where You Feel Stomach Pain
Even though the stomach is primarily a left-sided organ, stomach pain usually shows up in the epigastric region, the upper-middle area just below your breastbone. This happens because the nerves that serve the stomach enter the spinal cord at a central point, so your brain interprets the signal as coming from the middle rather than the left. Conditions like gastritis, ulcers, and acid reflux typically produce a burning or gnawing sensation in that central zone.
Pain that’s sharply localized to the left upper quadrant is more likely related to the spleen or the splenic flexure of the colon, though an enlarged or inflamed stomach can cause discomfort there too. If pain radiates from the upper middle toward the right side, the liver, gallbladder, or bile ducts are more common culprits. Knowing these general patterns helps you describe your symptoms more precisely if you ever need to.
Why the Stomach’s Position Shifts
The stomach is one of the more mobile organs in the abdomen. When empty, it’s roughly the size of your fist and sits high under the left ribs. After a large meal, it can stretch to hold about a liter of food and liquid, pushing downward and forward. Body position matters too: lying on your back lets the stomach settle toward the spine, while standing pulls it slightly lower due to gravity. In some people, especially those with a tall, thin build, the stomach hangs lower than average, a normal variation called gastroptosis that rarely causes problems on its own.
Pregnancy also shifts the stomach’s resting position. As the uterus expands upward during the second and third trimesters, it pushes the stomach higher and more to the left, which contributes to the heartburn many pregnant people experience.