Use the pressure checker above to narrow the cause

Answer three quick questions: whole house or one fixture, hot-only or both, and all day or only mornings/evenings. The live result names the most likely cause and gives you a 10-minute check you can do right now — no plumber visit yet.

Optional: add your city or ZIP to check if municipal peak demand is a factor in your area. The location stays on this page.

One fixture only: check the aerator or showerhead first

If pressure is weak at one sink or shower but fine everywhere else, the problem is usually local — not the whole system. The aerator (the screen at the faucet tip) collects sediment and mineral deposits over months. Unscrew it, rinse it, soak in vinegar if crusty, then reinstall. For showerheads, unscrew and flush the inlet screen the same way.

EPA WaterSense notes that simple maintenance like cleaning aerators can restore flow without replacing fixtures. This is a same-day fix for most renters and homeowners.

Hot-only low pressure: check the water heater shutoff valve

If only hot water is weak but cold is fine, the problem is between the heater and the fixture — not citywide. Common causes:

• Water heater shutoff valve partially closed (turn it fully open)
• Sediment in the heater tank restricting the outlet
• Old galvanized pipes on the hot side corroding faster than cold

Start by checking the shutoff valve at the heater inlet and outlet. If it is only cracked open, opening it fully can restore pressure immediately.

Whole house weak all day: pressure-reducing valve (PRV) or main shutoff

If every fixture is weak all the time — showers, sinks, outdoor hose — check two things:

1. Main shutoff valve near the meter: confirm it is fully open (handle parallel to the pipe). A partially closed valve starves the whole house.
2. Pressure-reducing valve (PRV) if you have one: these step high street pressure down to a safer 40–60 PSI. When a PRV ages, sticks, or is set too low, the whole house suffers. Adjusting or replacing it can restore normal pressure.

Use the PRV check guide to compare municipal PSI vs your home's target band and see if the valve needs service.

Only weak mornings/evenings: municipal peak demand

If pressure drops during morning showers or evening cooking but recovers midday or overnight, your utility may be delivering lower pressure during peak usage hours. Many municipal systems experience demand spikes when the neighborhood uses water at the same time.

This is common and often not a home problem. You can confirm by asking a neighbor if they notice the same pattern, or by checking your utility's website for known pressure zones or peak-hour guidance.

If you need steady pressure during peak hours, a booster pump can help — but confirm the diagnosis first before buying equipment.

Sudden drop with no obvious cause: hidden leak draining pressure

A hidden underground service-line leak or a major indoor break can steal pressure before water reaches fixtures. Warning signs:

• Sudden pressure drop with no fixture changes
• Wet ground near the meter or foundation
• Water bill spiked at the same time
• Meter moves with all fixtures off

Run a quiet-house meter test: turn everything off, read the meter, wait 15–30 minutes, read again. If it moved, you have continuous flow. That leak is draining pressure and costing money.

Check your bill if pressure and usage both changed

If low pressure started around the same time your water bill jumped, the two may be connected — a leak that wastes water and steals pressure, or a PRV failure that lets high street pressure through (raising usage and then later failing low). Upload your bill to see if usage spiked.