Toilet Not Level After Installation

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Quick answer
Confirm the symptom
Tools and prep
Step-by-step troubleshooting
Common causes table
Parts matching
When to call a pro
FAQ
Related guides

Quick answer

If your toilet is not level after installation, adjust the floor bolts and toilet base using a level. Tighten the bolts evenly and add shims if needed to stabilize the toilet.

Confirm the symptom

Toilet rocks or wobbles when sat on
Water pools unevenly in the bowl
Toilet base has visible gaps on one side
Sound of water sloshing when flushed

Tools and prep

Adjustable wrench
Plumber's putty
Level (bubble or digital)
Shims or cardboard
Screwdriver
Turn off water supply to the toilet
Protect floor with a towel or mat

Step-by-step troubleshooting

Check the Water Supply
Do: Turn off the water supply valve behind the toilet.
Observe: Water should stop flowing into the tank.
Means: The toilet is ready for adjustment without water pressure.
Next: Drain the toilet
Drain the Toilet
Do: Flush the toilet and hold the flapper open to drain remaining water.
Observe: Tank and bowl are mostly empty.
Means: Reduced water weight makes adjustment easier.
Next: Loosen floor bolts
Loosen Floor Bolts
Do: Use an adjustable wrench to loosen the nuts on the floor bolts without removing them.
Observe: Toilet base moves slightly when rocked.
Means: Bolts are loose enough for repositioning.
Next: Check level
Check Level
Do: Place a level across the toilet base and tank.
Observe: Toilet tilts to one side or is uneven.
Means: Adjustment is needed to stabilize the toilet.
Next: Adjust toilet position
Adjust Toilet Position
Do: Rock the toilet gently and shift it until it sits level. Add shims under the base if needed.
Observe: Toilet is stable and level.
Means: Toilet is properly aligned with the floor.
Next: Tighten bolts
Tighten Bolts
Do: Tighten the floor bolts evenly, alternating sides to avoid warping the base.
Observe: Toilet remains level and secure.
Means: Toilet is properly fastened to the floor.
Next: Reconnect water supply
Reconnect Water Supply
Do: Turn the water supply valve back on and let the tank refill.
Observe: Tank fills without leaks.
Means: Toilet is ready for use.
Next: Test the toilet
Test the Toilet
Do: Flush the toilet several times and check for rocking or leaks.
Observe: Toilet functions smoothly and remains level.
Means: Issue is resolved.
Next: Complete

Common causes

Cause	Likelihood	Difficulty	Part often needed
Uneven floor surface Toilet base sits unevenly if the floor is sloped or has debris.	Common	Easy	Shims
Loose or damaged floor bolts Bolts that are not tightened evenly or are worn can cause instability.	Common	Easy	Floor bolts
Improper wax ring installation A misaligned or compressed wax ring can cause the toilet to shift.	Sometimes	Medium	Wax ring
Warping of the toilet base Moisture or improper installation can cause the base to warp over time.	Rare	Hard	Toilet base repair
Incorrect toilet-to-floor alignment Toilet not centered over the flange can lead to rocking and instability.	Sometimes	Medium	Adjustment shims
Damaged flange A broken or improperly installed flange can prevent proper seating.	Rare	Hard	Toilet flange repair

Parts matching

Common parts needed to fix a toilet not level after installation:

Shims or cardboard for leveling
Plumber's putty for sealing gaps
New wax ring if the toilet shifts
Replacement floor bolts if worn or damaged
Toilet flange repair kit if the flange is damaged

Measure the gap between the toilet base and floor before purchasing shims or a new wax ring to ensure a proper fit.

When to call a professional

Toilet continues to rock after multiple adjustments
Water leaks persist after tightening bolts
Floor bolts are stripped or damaged beyond repair
Toilet base is cracked or warped
Flange is damaged or not aligned with the drain pipe

FAQ

Can I use anything besides shims to level my toilet?

Yes, you can use folded cardboard or plumber's putty to fill small gaps. However, shims provide a more stable and long-term solution.

How tight should I tighten the floor bolts?

Tighten the bolts just enough to secure the toilet without over-tightening, which can crack the porcelain. Alternate tightening both bolts gradually for even pressure.

Why is my toilet still rocking after I fixed it?

If the toilet still rocks, the floor may be uneven, or the flange might be damaged. Check for warping in the toilet base or re-level the floor with additional shims.

Do I need to replace the wax ring if I adjust the toilet?

If the toilet shifts significantly during adjustment, the wax ring may be compressed or misaligned. Replace it with a new wax ring to ensure a proper seal.