Last updated: 2026-05-01
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Toilet Running Constantly
Water keeps running into the bowl even when not flushed
95%
95% chance this is caused by:
Worn flapper valve or float set too high
🔧 The Exact Part You Need
Total parts cost: $20. Same-day shipping available on most items.
Easy · 5-10 minutes
Parts: $20 vs $$150-500 to replace
📋 Step-by-Step Instructions
1
Remove the tank lid
2
Check if the flapper is seating properly — if it's warped or has mineral buildup, replace it
3
Turn off water supply and flush to empty tank
4
Unclip old flapper, clip new one on
5
If flapper is fine, check the fill valve float height
6
Adjust float so water stops 1 inch below the overflow tube
7
If fill valve won't stop, replace the fill valve assembly
Other Toilet Problems
Frequently Asked Questions
How much does it cost to fix a toilet that's running constantly?
The part costs about $8. If you do it yourself, that's your total cost. A professional service call would add $100-200 in labor, bringing the total to $158.
How long does this toilet repair take?
This repair is rated "easy" and typically takes 5-10 minutes. The most time-consuming part is usually accessing the component, not the actual swap.
What if this isn't the problem?
Our diagnosis is 95% likely based on the symptom you described. If replacing this part doesn't fix it, the next most common cause for "water keeps running into the bowl even when not flushed" would be related to the wiring harness or control board. In that case, consider calling a professional.
Should I just replace my toilet instead?
A new toilet costs $150-500. If yours is well under 20-30 years (porcelain), 5-10 years (internal parts) old, a $8 repair is far more cost-effective. If it's near end-of-life and has had multiple issues, replacement starts making more sense.