Quick answer
If your toilet isn't emptying when flushed, check for a clogged trap or main drain line. Use a plunger or auger to clear the blockage. If the water level is too high, adjust the float or check for a faulty fill valve.
Confirm the symptom
- Toilet bowl water doesn't drain after flushing
- Water remains in the bowl even after multiple flushes
- Toilet gurgles or makes unusual noises during flush
- Water level in bowl is higher than usual
Tools and prep
- Rubber plunger
- Toilet auger (snake)
- Gloves
- Bucket
- Adjustable wrench
- Plumbing snake (for main line access)
- Turn off water supply to toilet
- Put on gloves to avoid contact with waste
Step-by-step troubleshooting
- Check for Obvious ClogsDo: Look into the toilet bowl for visible blockages like toilet paper, wipes, or foreign objects.Observe: If you see a clog, it's likely preventing proper drainage.Means: The clog is in the bowl or trapway.Next: Try plunging the toilet.
- Plunge the ToiletDo: Use a rubber plunger to create a tight seal around the drain hole and push and pull forcefully.Observe: If water starts to drain, the clog is partially cleared.Means: The clog is in the trap or lower drain line.Next: Flush the toilet to see if it drains completely.
- Use a Toilet AugerDo: Insert the auger into the drain hole and rotate the handle to break up or retrieve the clog.Observe: If water begins to drain, the clog is cleared.Means: The clog was in the trap or lower drain line.Next: Flush the toilet to ensure full drainage.
- Inspect Water LevelDo: Check the water level in the bowl after flushing. It should be about 1 inch below the overflow tube.Observe: If the water level is too high, it may be causing improper drainage.Means: The float or fill valve may need adjustment.Next: Adjust the float or fill valve.
- Adjust Float or Fill ValveDo: Turn off the water supply, flush the toilet to drain the tank, then adjust the float or fill valve to lower the water level.Observe: After adjustment, the water level should be correct and the toilet should drain properly.Means: The water level was too high, preventing proper drainage.Next: Turn the water supply back on and test the toilet.
- Check for Main Line ClogDo: If the toilet still doesn't drain, use a plumbing snake to check for a blockage in the main drain line.Observe: If the snake meets resistance, there's a blockage in the main line.Means: The main drain line is clogged.Next: Call a professional plumber to clear the main line.
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Clogged trap or drain line Debris, toilet paper, or non-flushable items can block the trap or main drain. | Common | Easy–Medium | Toilet auger |
| High water level in bowl An improperly adjusted float or faulty fill valve can cause the bowl water level to be too high, reducing drainage efficiency. | Sometimes | Easy | Fill valve or float adjustment |
| Faulty flapper or flush valve A damaged or improperly seated flapper can prevent the tank from emptying fully, leading to poor bowl drainage. | Sometimes | Easy–Medium | Flapper or flush valve |
| Mineral buildup or blockage in trapway Hard water can cause mineral deposits that restrict water flow in the trapway. | Sometimes | Medium | Toilet cleaner or auger |
| Main sewer line clog Tree roots, grease, or debris can block the main sewer line, affecting multiple drains. | Rare | Hard | Plumbing snake or professional service |
| Incorrect water level in tank If the tank water level is too low, it may not provide enough force to fully flush the bowl. | Sometimes | Easy | Fill valve adjustment |
Parts matching
Common parts needed to fix a toilet not emptying when flushed include:
- Toilet auger for clearing clogs in the trap or drain line
- Rubber plunger for initial clog removal
- Fill valve or float adjustment kit for correcting water levels
- Flapper or flush valve if the tank isn't emptying properly
- Plumbing snake for main line clogs
Always turn off the water supply before making adjustments or repairs to the toilet.
When to call a professional
- The toilet still doesn't drain after using a plunger and auger
- You suspect a main sewer line clog or tree root intrusion
- You hear gurgling sounds from other drains or the toilet
- Water is backing up into the bowl or other fixtures
- You're unsure about making adjustments to the toilet's internal components
- The problem persists after multiple attempts to fix it
FAQ
Why won't my toilet flush all the way?
This can be caused by a clog in the trap or drain line, a high water level in the bowl, or a faulty flapper or fill valve.
How do I know if my toilet is clogged?
Signs include water not draining after flushing, gurgling noises, and a higher-than-normal water level in the bowl.
Can I use a plunger to fix a toilet that won't empty?
Yes, a plunger can often clear minor clogs in the trap or drain line. Use a flange plunger for best results.
What should I do if my toilet is overflowing but not clogged?
Check the water level in the tank and bowl. If it's too high, adjust the float or fill valve. If the problem continues, there may be an issue with the wax ring or main drain line.
How do I adjust the water level in my toilet tank?
Turn off the water supply, flush the toilet to drain the tank, then adjust the float or fill valve until the water level is about 1 inch below the overflow tube.