Where the problem usually starts

Low shower pressure most often comes from a clogged showerhead, a closed or partially closed shut-off valve, or mineral buildup in the pipes feeding your shower. Before you call a plumber, check three things: whether other fixtures in your home have normal pressure, whether the shut-off valve under the sink or behind the wall is fully open, and whether your showerhead is visibly clogged with white or brown deposits.

If only your shower is weak but your kitchen sink and bathroom sink run at normal pressure, the problem is almost certainly in the showerhead itself or the short pipe section that feeds it. If your whole house has low pressure, the issue is upstream — in the main line, the meter, or the pressure regulator.

Key Takeaways

  • A clogged showerhead is the most common cause and takes 20 minutes to clean with vinegar and a toothpick.
  • Check that the shut-off valve under your sink or in the wall is turned fully counterclockwise; a half-open valve cuts pressure in half.
  • If only your shower is weak, the problem is in the showerhead or the short supply line; if your whole house is weak, call your water company to check the main line.
  • Mineral buildup in old pipes may require a plumber to replace the supply line, which costs $200 to $500 depending on how much pipe needs removal.

Cleaning a clogged showerhead

Unscrew your showerhead by hand or with a wrench if it is stuck. Look at the face where water comes out — if you see white, tan, or rust-colored deposits, soak the head in white vinegar for two to four hours. For heavy buildup, leave it overnight.

After soaking, use an old toothbrush to scrub the face and the holes. A straightened paperclip or a small nail works to poke out any holes that are still blocked. Rinse under hot tap water, screw it back on, and test. If pressure is still low, soak again for longer or replace the showerhead entirely — a new one costs $15 to $40 and takes 30 seconds to install.

Opening a shut-off valve that is partially closed

Look under your bathroom sink or in the wall behind it for a small valve with a handle. The handle should point in the same direction as the pipe — if it points sideways or at an angle, it is not fully open. Turn it counterclockwise until it stops, then test your shower.

If you cannot find a shut-off valve under the sink, look in the wall behind the shower or in a basement or crawl space below the bathroom. Some homes have a main shut-off valve near the water meter that controls the whole house; if that is partially closed, every fixture will have weak pressure. Turn it fully counterclockwise. If the handle is stuck or will not turn, do not force it — call a plumber to avoid breaking the valve.

Checking for mineral buildup in supply lines

If your showerhead is clean and the shut-off valve is fully open but pressure is still low, mineral deposits may be blocking the supply line inside the wall. This is more common in homes with hard water or in areas where the water supply is mineral-heavy. You cannot clear this yourself without opening the wall.

A plumber can run a camera through the line to confirm the blockage, then either flush the line with a chemical descaler or replace the section of pipe. Replacement usually costs $200 to $500 depending on how much pipe needs to come out and whether it is accessible. If you have hard water throughout your home, a whole-house water softener ($500 to $2,500 installed) will prevent future buildup in all your pipes and fixtures.

Replacing an old or restrictive showerhead

Some showerheads are designed to restrict flow to save water — they may have a flow limiter inside that you cannot remove without breaking the head. If your showerhead is more than 10 years old or was installed in a water-conservation retrofit, it may be limiting you to 2 gallons per minute when a standard head allows 2.5 gallons per minute.

Buy a new showerhead rated for at least 2.5 gallons per minute. Unscrew the old one by hand or with a wrench, wrap the threads of the new one with plumber's tape (also called Teflon tape) to prevent leaks, and screw it on hand-tight. Test it. If pressure is still weak after a new head, the problem is in the supply line or the main water system, not the showerhead.

When to call a plumber

Call a plumber if the shut-off valve will not turn, if your whole house has low pressure and the main shut-off valve is already fully open, or if only your shower is weak after you have cleaned the showerhead and checked the shut-off valve. A plumber can test the pressure with a gauge, identify whether the problem is in the supply line or the main system, and recommend whether you need a line replacement, a new pressure regulator, or a call to your water company.

If you rent, contact your landlord or property manager before attempting any repairs. They are responsible for fixing the plumbing, and opening walls or replacing pipes requires a licensed plumber in most places.

What to expect from your water company

If your whole house has low pressure and your main shut-off valve is fully open, your water company may be delivering low pressure to your meter. Call them and ask them to test the pressure at the meter — they do this for free. If the pressure is below 40 pounds per square inch, they may adjust the regulator on your side of the meter or investigate a problem in the main line.

Some water companies have scheduled maintenance that temporarily lowers pressure in a neighborhood. If you notice low pressure in your whole house, check your water company's website or call their customer service line to see whether work is happening in your area. Pressure usually returns to normal within a few hours.

Frequently Asked Questions

Can I increase water pressure by adjusting something in my home?

Yes, if you have a pressure regulator — a bell-shaped device on the main water line where it enters your home. It has a screw on top that you can turn clockwise to increase pressure. Turn it a quarter turn, wait a few minutes, and test. Do not turn it more than a half turn without a pressure gauge, or you may damage fixtures or pipes. If you are unsure where it is, a plumber can locate and adjust it for $100 to $150.

Will cleaning my showerhead really make a big difference?

Yes. A showerhead clogged with mineral deposits can reduce pressure by 50 percent or more. Vinegar soaking and a toothbrush take 20 minutes and cost nothing. If that restores your pressure, you have solved the problem. If not, you know the issue is elsewhere.

Is low shower pressure a sign of a bigger plumbing problem?

Not always. A clogged showerhead or a partially closed valve is a small, cheap fix. But if your whole house has low pressure or if your shower pressure dropped suddenly, it may signal a leak in the main line or a failing pressure regulator. A plumber can diagnose this in one visit.

How much does it cost to replace a shower supply line?

If the line is accessible — for example, in a basement or crawl space — replacement usually costs $200 to $500. If the plumber has to open a wall or ceiling to reach it, the cost can be higher. Get a quote from two plumbers before deciding.